diff --git a/kotlin-utils/build.gradle.kts b/kotlin-utils/build.gradle.kts
index 6754fed4..0fa3b6e0 100644
--- a/kotlin-utils/build.gradle.kts
+++ b/kotlin-utils/build.gradle.kts
@@ -6,7 +6,7 @@ plugins {
 }
 
 group = "xyz.lbres"
-version = "0.2.1"
+version = "0.3.0"
 
 repositories {
     mavenCentral()
diff --git a/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/char/ext/CharExt.kt b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/char/ext/CharExt.kt
new file mode 100644
index 00000000..59ece31d
--- /dev/null
+++ b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/char/ext/CharExt.kt
@@ -0,0 +1,19 @@
+package xyz.lbres.kotlinutils.char.ext
+
+import xyz.lbres.kotlinutils.general.ternaryIf
+import xyz.lbres.kotlinutils.int.ext.isZero
+
+/**
+ * Returns this number if not zero, or the result of calling [getDefaultValue] if it is.
+ *
+ * @param getDefaultValue () -> [Char]
+ * @return [Char] the current value, or the default
+ */
+fun Char.ifZero(getDefaultValue: () -> Char): Char = ternaryIf(isZero(), getDefaultValue(), this)
+
+/**
+ * Unary check to determine if value is zero
+ *
+ * @return [Boolean]: true if value is zero, false otherwise
+ */
+fun Char.isZero(): Boolean = code.isZero()
diff --git a/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/collection/char/ext/CharCollectionExt.kt b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/collection/char/ext/CharCollectionExt.kt
new file mode 100644
index 00000000..61e0ee89
--- /dev/null
+++ b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/collection/char/ext/CharCollectionExt.kt
@@ -0,0 +1,30 @@
+package xyz.lbres.kotlinutils.collection.char.ext
+
+import xyz.lbres.kotlinutils.char.ext.isZero
+
+/**
+ * Filter a char collection to contain only elements that do not equal zero.
+ *
+ * @return [Collection]<[Char]>: collection containing the same values as [this], except any elements with value 0.
+ */
+fun Collection<Char>.filterNotZero(): Collection<Char> = filterNot { it.isZero() }
+
+/**
+ * Add all values in collection.
+ *
+ * @return [Char]: sum of numbers in collection
+ */
+fun Collection<Char>.sum(): Char = fold(Char(0)) { acc, char -> acc + char.code }
+
+/**
+ * Multiply all values in collection
+ *
+ * @return [Char]: product of numbers in collection, or 0 if collection is empty
+ */
+fun Collection<Char>.product(): Char {
+    if (isEmpty()) {
+        return Char(0)
+    }
+
+    return fold(1) { acc, char -> acc * char.code }.toChar()
+}
diff --git a/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/collection/ext/CollectionExt.kt b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/collection/ext/CollectionExt.kt
index 1856fd16..0c1af2f8 100644
--- a/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/collection/ext/CollectionExt.kt
+++ b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/collection/ext/CollectionExt.kt
@@ -4,7 +4,8 @@ import xyz.lbres.kotlinutils.classes.multiset.MultiSet
 import xyz.lbres.kotlinutils.classes.multiset.MultiSetImpl
 import xyz.lbres.kotlinutils.classes.multiset.MutableMultiSet
 import xyz.lbres.kotlinutils.classes.multiset.MutableMultiSetImpl
-import xyz.lbres.kotlinutils.int.ext.isZero
+import xyz.lbres.kotlinutils.generic.ext.isNotNull
+import xyz.lbres.kotlinutils.generic.ext.isNull
 
 /**
  * Create a MultiSet with the elements in the current collection.
@@ -21,8 +22,23 @@ fun <E> Collection<E>.toMultiSet(): MultiSet<E> = MultiSetImpl(this)
 fun <E> Collection<E>.toMutableMultiSet(): MutableMultiSet<E> = MutableMultiSetImpl(this)
 
 /**
- * Filter an integer collection to contain only elements that do not equal zero.
+ * Count number of elements in the collection that are null.
  *
- * @return [Collection<Int>]: collection containing the same values as [this], except any elements with value 0.
+ * @return [Int]
  */
-fun Collection<Int>.filterNotZero() = filterNot { it.isZero() }
+fun <E> Collection<E?>.countNull(): Int = count { it.isNull() }
+
+/**
+ * Count number of elements in the collection that are not null.
+ *
+ * @return [Int]
+ */
+fun <E> Collection<E?>.countNotNull(): Int = count { it.isNotNull() }
+
+/**
+ * Check if a collection is not null and is not empty.
+ * Combines separate calls for checking if the collection is null and if it is empty.
+ *
+ * @return [Boolean]: true if the collection is not null and has size > 0, false otherwise
+ */
+fun <E> Collection<E>?.isNotNullOrEmpty() = !this.isNullOrEmpty()
diff --git a/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/collection/int/ext/IntCollectionExt.kt b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/collection/int/ext/IntCollectionExt.kt
new file mode 100644
index 00000000..e9570964
--- /dev/null
+++ b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/collection/int/ext/IntCollectionExt.kt
@@ -0,0 +1,25 @@
+package xyz.lbres.kotlinutils.collection.int.ext
+
+import xyz.lbres.kotlinutils.general.ternaryIf
+import xyz.lbres.kotlinutils.int.ext.isZero
+
+/**
+ * Filter an integer collection to contain only elements that do not equal zero.
+ *
+ * @return [Collection]<[Int]>: collection containing the same values as [this], except any elements with value 0.
+ */
+fun Collection<Int>.filterNotZero(): Collection<Int> = filterNot { it.isZero() }
+
+/**
+ * Add all values in collection.
+ *
+ * @return [Int]: sum of numbers in collection
+ */
+fun Collection<Int>.sum(): Int = fold(0, Int::plus)
+
+/**
+ * Multiply all values in collection
+ *
+ * @return [Int]: product of numbers in collection, or 0 if collection is empty
+ */
+fun Collection<Int>.product(): Int = ternaryIf(isEmpty(), 0, fold(1, Int::times))
diff --git a/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/collection/long/ext/LongCollectionExt.kt b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/collection/long/ext/LongCollectionExt.kt
new file mode 100644
index 00000000..a68c5051
--- /dev/null
+++ b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/collection/long/ext/LongCollectionExt.kt
@@ -0,0 +1,25 @@
+package xyz.lbres.kotlinutils.collection.long.ext
+
+import xyz.lbres.kotlinutils.general.ternaryIf
+import xyz.lbres.kotlinutils.long.ext.isZero
+
+/**
+ * Filter a long collection to contain only elements that do not equal zero.
+ *
+ * @return [Collection]<[Long]>: collection containing the same values as [this], except any elements with value 0.
+ */
+fun Collection<Long>.filterNotZero(): Collection<Long> = filterNot { it.isZero() }
+
+/**
+ * Add all values in collection.
+ *
+ * @return [Long]: sum of numbers in collection
+ */
+fun Collection<Long>.sum(): Long = fold(0, Long::plus)
+
+/**
+ * Multiply all values in collection
+ *
+ * @return [Long]: product of numbers in collection, or 0 if collection is empty
+ */
+fun Collection<Long>.product(): Long = ternaryIf(isEmpty(), 0, fold(1, Long::times))
diff --git a/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/generic/ext/GenericExt.kt b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/generic/ext/GenericExt.kt
index 733d4f11..f0b5b343 100644
--- a/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/generic/ext/GenericExt.kt
+++ b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/generic/ext/GenericExt.kt
@@ -7,3 +7,17 @@ package xyz.lbres.kotlinutils.generic.ext
  * @return [T] the current value, or the default
  */
 fun <T> T?.ifNull(getDefaultValue: () -> T): T = this ?: getDefaultValue()
+
+/**
+ * Returns true if a value is null, or false otherwise
+ *
+ * @return [Boolean]
+ */
+fun <T> T?.isNull(): Boolean = this == null
+
+/**
+ * Returns true if a value is not null, or false otherwise
+ *
+ * @return [Boolean]
+ */
+fun <T> T?.isNotNull(): Boolean = this != null
diff --git a/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/int/ext/IntExt.kt b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/int/ext/IntExt.kt
index 98b4deab..a88ecc42 100644
--- a/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/int/ext/IntExt.kt
+++ b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/int/ext/IntExt.kt
@@ -1,18 +1,14 @@
 package xyz.lbres.kotlinutils.int.ext
 
+import xyz.lbres.kotlinutils.general.ternaryIf
+
 /**
  * Returns this number if not zero, or the result of calling [getDefaultValue] if it is.
  *
- * @param getDefaultValue [() -> Int]
+ * @param getDefaultValue () -> [Int]
  * @return [Int] the current value, or the default
  */
-fun Int.ifZero(getDefaultValue: () -> Int): Int {
-    return if (equals(0)) {
-        getDefaultValue()
-    } else {
-        this
-    }
-}
+fun Int.ifZero(getDefaultValue: () -> Int): Int = ternaryIf(isZero(), getDefaultValue(), this)
 
 /**
  * Unary check to determine if value is zero
diff --git a/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/long/ext/LongExt.kt b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/long/ext/LongExt.kt
new file mode 100644
index 00000000..eb92410f
--- /dev/null
+++ b/kotlin-utils/src/main/kotlin/xyz/lbres/kotlinutils/long/ext/LongExt.kt
@@ -0,0 +1,25 @@
+package xyz.lbres.kotlinutils.long.ext
+
+import xyz.lbres.kotlinutils.general.ternaryIf
+
+/**
+ * Returns this number if not zero, or the result of calling [getDefaultValue] if it is.
+ *
+ * @param getDefaultValue () -> [Long]
+ * @return [Long] the current value, or the default
+ */
+fun Long.ifZero(getDefaultValue: () -> Long): Long = ternaryIf(isZero(), getDefaultValue(), this)
+
+/**
+ * Unary check to determine if value is zero
+ *
+ * @return [Boolean]: true if value is zero, false otherwise
+ */
+fun Long.isZero(): Boolean = equals(0L)
+
+/**
+ * Unary check to determine if value is negative
+ *
+ * @return [Boolean]: true if value is less than zero, false otherwise
+ */
+fun Long.isNegative(): Boolean = this < 0L
diff --git a/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/char/ext/CharExtTest.kt b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/char/ext/CharExtTest.kt
new file mode 100644
index 00000000..7c3ce374
--- /dev/null
+++ b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/char/ext/CharExtTest.kt
@@ -0,0 +1,37 @@
+package xyz.lbres.kotlinutils.char.ext
+
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+internal class CharExtTest {
+    @Test
+    internal fun testIfZero() {
+        val getValue = { Char(2) }
+
+        var char = Char(0)
+        var expected = Char(2)
+        assertEquals(expected, char.ifZero(getValue))
+
+        char = Char(2)
+        expected = Char(2)
+        assertEquals(expected, char.ifZero(getValue))
+
+        char = Char(15)
+        expected = Char(15)
+        assertEquals(expected, char.ifZero(getValue))
+    }
+
+    @Test
+    internal fun testIsZero() {
+        var char = Char(0)
+        assertTrue(char.isZero())
+
+        char = Char(1)
+        assertFalse(char.isZero())
+
+        char = Char(100)
+        assertFalse(char.isZero())
+    }
+}
diff --git a/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/collection/char/ext/CharCollectionExtTest.kt b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/collection/char/ext/CharCollectionExtTest.kt
new file mode 100644
index 00000000..245ecb3a
--- /dev/null
+++ b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/collection/char/ext/CharCollectionExtTest.kt
@@ -0,0 +1,68 @@
+package xyz.lbres.kotlinutils.collection.char.ext
+
+import kotlin.test.Test
+import kotlin.test.assertEquals
+
+internal class CharCollectionExtTest {
+    private val zero = Char(0)
+    private val one = Char(1)
+    private val four = Char(4)
+    private val five = Char(5)
+
+    @Test
+    internal fun testFilterNotZero() {
+        var list: List<Char> = listOf()
+        var expected: List<Char> = listOf()
+        assertEquals(expected, list.filterNotZero())
+
+        list = listOf(zero, zero, zero)
+        expected = listOf()
+        assertEquals(expected, list.filterNotZero())
+
+        list = listOf(one, Char(2), zero, four, zero, zero, five)
+        expected = listOf(one, Char(2), four, five)
+        assertEquals(expected, list.filterNotZero())
+
+        list = listOf(one, four, Char(1000), Char(19), five)
+        expected = listOf(one, four, Char(1000), Char(19), five)
+        assertEquals(expected, list.filterNotZero())
+    }
+
+    @Test
+    internal fun testSum() {
+        var list: List<Char> = emptyList()
+        var expected = zero
+        assertEquals(expected, list.sum())
+
+        list = listOf(Char(33))
+        expected = Char(33)
+        assertEquals(expected, list.sum())
+
+        list = listOf(Char(100), Char(45), Char(10), Char(67), Char(99))
+        expected = Char(321)
+        assertEquals(expected, list.sum())
+    }
+
+    @Test
+    internal fun testProduct() {
+        var list: List<Char> = emptyList()
+        var expected = zero
+        assertEquals(expected, list.product())
+
+        list = listOf(zero)
+        expected = zero
+        assertEquals(expected, list.product())
+
+        list = listOf(one)
+        expected = one
+        assertEquals(expected, list.product())
+
+        list = listOf(four, four, zero)
+        expected = zero
+        assertEquals(expected, list.product())
+
+        list = listOf(Char(15), Char(23), Char(4), Char(4))
+        expected = Char(5520)
+        assertEquals(expected, list.product())
+    }
+}
diff --git a/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/collection/ext/CollectionExtTest.kt b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/collection/ext/CollectionExtTest.kt
index 5f64505d..105c6d35 100644
--- a/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/collection/ext/CollectionExtTest.kt
+++ b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/collection/ext/CollectionExtTest.kt
@@ -6,6 +6,8 @@ import xyz.lbres.kotlinutils.classes.multiset.multiSetOf
 import xyz.lbres.kotlinutils.classes.multiset.mutableMultiSetOf
 import kotlin.test.Test
 import kotlin.test.assertEquals
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
 
 internal class CollectionExtTest {
     @Test
@@ -61,25 +63,66 @@ internal class CollectionExtTest {
     }
 
     @Test
-    internal fun testFilterNotZero() {
-        var list: List<Int> = listOf()
-        var expected: List<Int> = listOf()
-        assertEquals(expected, list.filterNotZero())
-
-        list = listOf(0, 0, 0)
-        expected = listOf()
-        assertEquals(expected, list.filterNotZero())
-
-        list = listOf(1, 2, 0, 4, 0, 0, 5)
-        expected = listOf(1, 2, 4, 5)
-        assertEquals(expected, list.filterNotZero())
-
-        list = listOf(-1, 1, 0)
-        expected = listOf(-1, 1)
-        assertEquals(expected, list.filterNotZero())
-
-        list = listOf(1, 4, 1000, 19, 5)
-        expected = listOf(1, 4, 1000, 19, 5)
-        assertEquals(expected, list.filterNotZero())
+    internal fun testCountNull() {
+        var collection: Collection<Int?> = listOf()
+        var expected = 0
+        assertEquals(expected, collection.countNull())
+
+        collection = listOf(1, 2, 3, 4, 5)
+        expected = 0
+        assertEquals(expected, collection.countNull())
+
+        collection = setOf(1, null, 2, 3, 4)
+        expected = 1
+        assertEquals(expected, collection.countNull())
+
+        collection = listOf(null, null, null, 4, 5, 6, null)
+        expected = 4
+        assertEquals(expected, collection.countNull())
+
+        collection = listOf(null, null)
+        expected = 2
+        assertEquals(expected, collection.countNull())
+    }
+
+    @Test
+    internal fun testCountNotNull() {
+        var collection: Collection<Int?> = listOf()
+        var expected = 0
+        assertEquals(expected, collection.countNotNull())
+
+        collection = listOf(null, null)
+        expected = 0
+        assertEquals(expected, collection.countNotNull())
+
+        collection = setOf(1, null, 2, 3, 4)
+        expected = 4
+        assertEquals(expected, collection.countNotNull())
+
+        collection = listOf(null, null, null, 4, 5, 6, null)
+        expected = 3
+        assertEquals(expected, collection.countNotNull())
+
+        collection = listOf(1, 2, 3, 4, 5)
+        expected = 5
+        assertEquals(expected, collection.countNotNull())
+    }
+
+    @Test
+    internal fun testIsNotNullOrEmpty() {
+        var collection: Collection<Int?>? = null
+        assertFalse(collection.isNotNullOrEmpty())
+
+        collection = setOf()
+        assertFalse(collection.isNotNullOrEmpty())
+
+        collection = listOf(1)
+        assertTrue(collection.isNotNullOrEmpty())
+
+        collection = listOf(null)
+        assertTrue(collection.isNotNullOrEmpty())
+
+        collection = listOf(1, 2, 3)
+        assertTrue(collection.isNotNullOrEmpty())
     }
 }
diff --git a/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/collection/int/ext/IntCollectionExtTest.kt b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/collection/int/ext/IntCollectionExtTest.kt
new file mode 100644
index 00000000..c3b9a3d8
--- /dev/null
+++ b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/collection/int/ext/IntCollectionExtTest.kt
@@ -0,0 +1,88 @@
+package xyz.lbres.kotlinutils.collection.int.ext
+
+import xyz.lbres.kotlinutils.list.IntList
+import kotlin.test.Test
+import kotlin.test.assertEquals
+
+class IntCollectionExtTest {
+    @Test
+    internal fun testFilterNotZero() {
+        var list: List<Int> = listOf()
+        var expected: List<Int> = listOf()
+        assertEquals(expected, list.filterNotZero())
+
+        list = listOf(0, 0, 0)
+        expected = listOf()
+        assertEquals(expected, list.filterNotZero())
+
+        list = listOf(1, 2, 0, 4, 0, 0, 5)
+        expected = listOf(1, 2, 4, 5)
+        assertEquals(expected, list.filterNotZero())
+
+        list = listOf(-1, 1, 0)
+        expected = listOf(-1, 1)
+        assertEquals(expected, list.filterNotZero())
+
+        list = listOf(1, 4, 1000, 19, 5)
+        expected = listOf(1, 4, 1000, 19, 5)
+        assertEquals(expected, list.filterNotZero())
+    }
+
+    @Test
+    internal fun testSum() {
+        var list: IntList = emptyList()
+        var expected = 0
+        assertEquals(expected, list.sum())
+
+        list = listOf(33)
+        expected = 33
+        assertEquals(expected, list.sum())
+
+        list = listOf(-33)
+        expected = -33
+        assertEquals(expected, list.sum())
+
+        list = listOf(5, -5)
+        expected = 0
+        assertEquals(expected, list.sum())
+
+        list = listOf(100, 45, -10, 67, 99)
+        expected = 301
+        assertEquals(expected, list.sum())
+
+        list = listOf(-100, 45, -10, -67, 99)
+        expected = -33
+        assertEquals(expected, list.sum())
+    }
+
+    @Test
+    internal fun testProduct() {
+        var list: IntList = emptyList()
+        var expected = 0
+        assertEquals(expected, list.product())
+
+        list = listOf(0)
+        expected = 0
+        assertEquals(expected, list.product())
+
+        list = listOf(1)
+        expected = 1
+        assertEquals(expected, list.product())
+
+        list = listOf(-1)
+        expected = -1
+        assertEquals(expected, list.product())
+
+        list = listOf(5, 5, -2, 0)
+        expected = 0
+        assertEquals(expected, list.product())
+
+        list = listOf(-15, 23, 17, 4, 4, -2, 3)
+        expected = 563040
+        assertEquals(expected, list.product())
+
+        list = listOf(-15, 23, 17, 4, 4, -2, -3)
+        expected = -563040
+        assertEquals(expected, list.product())
+    }
+}
diff --git a/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/collection/long/ext/LongCollectionExtTest.kt b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/collection/long/ext/LongCollectionExtTest.kt
new file mode 100644
index 00000000..730b00e5
--- /dev/null
+++ b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/collection/long/ext/LongCollectionExtTest.kt
@@ -0,0 +1,87 @@
+package xyz.lbres.kotlinutils.collection.long.ext
+
+import kotlin.test.Test
+import kotlin.test.assertEquals
+
+internal class LongCollectionExtTest {
+    @Test
+    internal fun testFilterNotZero() {
+        var list: List<Long> = listOf()
+        var expected: List<Long> = listOf()
+        assertEquals(expected, list.filterNotZero())
+
+        list = listOf(0, 0, 0)
+        expected = listOf()
+        assertEquals(expected, list.filterNotZero())
+
+        list = listOf(1, 2, 0, 4, 0, 0, 5)
+        expected = listOf(1, 2, 4, 5)
+        assertEquals(expected, list.filterNotZero())
+
+        list = listOf(-1, 1, 0)
+        expected = listOf(-1, 1)
+        assertEquals(expected, list.filterNotZero())
+
+        list = listOf(1, 4, 1000, 19, 5)
+        expected = listOf(1, 4, 1000, 19, 5)
+        assertEquals(expected, list.filterNotZero())
+    }
+
+    @Test
+    internal fun testSum() {
+        var list: List<Long> = emptyList()
+        var expected = 0L
+        assertEquals(expected, list.sum())
+
+        list = listOf(33)
+        expected = 33
+        assertEquals(expected, list.sum())
+
+        list = listOf(-33)
+        expected = -33
+        assertEquals(expected, list.sum())
+
+        list = listOf(5, -5)
+        expected = 0
+        assertEquals(expected, list.sum())
+
+        list = listOf(100, 45, -10, 67, 99)
+        expected = 301
+        assertEquals(expected, list.sum())
+
+        list = listOf(-100, 45, -10, -67, 99)
+        expected = -33
+        assertEquals(expected, list.sum())
+    }
+
+    @Test
+    internal fun testProduct() {
+        var list: List<Long> = emptyList()
+        var expected = 0L
+        assertEquals(expected, list.product())
+
+        list = listOf(0)
+        expected = 0
+        assertEquals(expected, list.product())
+
+        list = listOf(1)
+        expected = 1
+        assertEquals(expected, list.product())
+
+        list = listOf(-1)
+        expected = -1
+        assertEquals(expected, list.product())
+
+        list = listOf(5, 5, -2, 0)
+        expected = 0
+        assertEquals(expected, list.product())
+
+        list = listOf(-15, 23, 17, 4, 4, -2, 3)
+        expected = 563040
+        assertEquals(expected, list.product())
+
+        list = listOf(-15, 23, 17, 4, 4, -2, -3)
+        expected = -563040
+        assertEquals(expected, list.product())
+    }
+}
diff --git a/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/generic/ext/GenericExtTest.kt b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/generic/ext/GenericExtTest.kt
index ea4c46a2..020795d0 100644
--- a/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/generic/ext/GenericExtTest.kt
+++ b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/generic/ext/GenericExtTest.kt
@@ -2,6 +2,8 @@ package xyz.lbres.kotlinutils.generic.ext
 
 import kotlin.test.Test
 import kotlin.test.assertEquals
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
 
 internal class GenericExtTest {
     @Test
@@ -56,4 +58,58 @@ internal class GenericExtTest {
         val resultErr = error.ifNull { expectedErr }
         assertEquals(expectedErr, resultErr)
     }
+
+    @Test
+    fun testIsNull() {
+        var string: String? = null
+        assertTrue(string.isNull())
+
+        string = ""
+        assertFalse(string.isNull())
+
+        string = "null"
+        assertFalse(string.isNull())
+
+        string = "abc 123"
+        assertFalse(string.isNull())
+
+        var int: Int? = null
+        assertTrue(int.isNull())
+
+        int = -100
+        assertFalse(int.isNull())
+
+        var list: List<Int?>? = null
+        assertTrue(list.isNull())
+
+        list = listOf(null, null)
+        assertFalse(list.isNull())
+    }
+
+    @Test
+    fun testIsNotNull() {
+        var string: String? = null
+        assertFalse(string.isNotNull())
+
+        string = ""
+        assertTrue(string.isNotNull())
+
+        string = "null"
+        assertTrue(string.isNotNull())
+
+        string = "abc 123"
+        assertTrue(string.isNotNull())
+
+        var int: Int? = null
+        assertFalse(int.isNotNull())
+
+        int = -100
+        assertTrue(int.isNotNull())
+
+        var list: List<Int?>? = null
+        assertFalse(list.isNotNull())
+
+        list = listOf(null, null)
+        assertTrue(list.isNotNull())
+    }
 }
diff --git a/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/long/ext/LongExtTest.kt b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/long/ext/LongExtTest.kt
new file mode 100644
index 00000000..23980e01
--- /dev/null
+++ b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/long/ext/LongExtTest.kt
@@ -0,0 +1,65 @@
+package xyz.lbres.kotlinutils.long.ext
+
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+class LongExtTest {
+    @Test
+    internal fun testIfZero() {
+        val getValue = { 2L }
+
+        var long = 0L
+        var expected = 2L
+        assertEquals(expected, long.ifZero(getValue))
+
+        long = 2
+        expected = 2
+        assertEquals(expected, long.ifZero(getValue))
+
+        long = 15
+        expected = 15
+        assertEquals(expected, long.ifZero(getValue))
+
+        long = -100
+        expected = -100
+        assertEquals(expected, long.ifZero(getValue))
+    }
+
+    @Test
+    internal fun testIsNegative() {
+        var long = 0L
+        assertFalse(long.isNegative())
+
+        long = 1L
+        assertFalse(long.isNegative())
+
+        long = 100
+        assertFalse(long.isNegative())
+
+        long = -1
+        assertTrue(long.isNegative())
+
+        long = -100
+        assertTrue(long.isNegative())
+    }
+
+    @Test
+    internal fun testIsZero() {
+        var long = 0L
+        assertTrue(long.isZero())
+
+        long = 1
+        assertFalse(long.isZero())
+
+        long = -1
+        assertFalse(long.isZero())
+
+        long = 100
+        assertFalse(long.isZero())
+
+        long = -100
+        assertFalse(long.isZero())
+    }
+}
diff --git a/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/testHelpers.kt b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/testHelpers.kt
index 0e0c66d2..246ef4fd 100644
--- a/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/testHelpers.kt
+++ b/kotlin-utils/src/test/kotlin/xyz/lbres/kotlinutils/testHelpers.kt
@@ -34,7 +34,7 @@ internal fun <T> runRandomTest(randomAction: () -> T, randomCheck: (T) -> Boolea
  */
 internal fun <T> runTestWithWeights(weightedItems: WeightedList<T>, randomAction: () -> T) {
     val iterations = 1000
-    val errorRange = 0.05f
+    val errorRange = 0.075f
 
     // run action and collect results
     val results = List(iterations) { randomAction() }