diff --git a/X10D/src/Math/ByteExtensions.cs b/X10D/src/Math/ByteExtensions.cs
index 310c4e4..ca68dd6 100644
--- a/X10D/src/Math/ByteExtensions.cs
+++ b/X10D/src/Math/ByteExtensions.cs
@@ -73,7 +73,7 @@ public static class ByteExtensions
 #endif
     public static bool IsEven(this byte value)
     {
-        return value % 2 == 0;
+        return (value & 1) == 0;
     }
 
     /// <summary>
diff --git a/X10D/src/Math/Int64Extensions.cs b/X10D/src/Math/Int64Extensions.cs
index 01f10fa..fdb920b 100644
--- a/X10D/src/Math/Int64Extensions.cs
+++ b/X10D/src/Math/Int64Extensions.cs
@@ -121,7 +121,7 @@ public static class Int64Extensions
             case <= 3: return true;
         }
 
-        if (value % 2 == 0 || value % 3 == 0)
+        if ((value & 1) == 0 || value % 3 == 0)
         {
             return false;
         }
diff --git a/X10D/src/Math/SByteExtensions.cs b/X10D/src/Math/SByteExtensions.cs
index 07252ef..f77d56d 100644
--- a/X10D/src/Math/SByteExtensions.cs
+++ b/X10D/src/Math/SByteExtensions.cs
@@ -79,7 +79,7 @@ public static class SByteExtensions
 #endif
     public static bool IsEven(this sbyte value)
     {
-        return value % 2 == 0;
+        return (value & 1) == 0;
     }
 
     /// <summary>
diff --git a/X10D/src/Math/UInt64Extensions.cs b/X10D/src/Math/UInt64Extensions.cs
index f081236..9d2efbc 100644
--- a/X10D/src/Math/UInt64Extensions.cs
+++ b/X10D/src/Math/UInt64Extensions.cs
@@ -1,4 +1,4 @@
-using System.Diagnostics.Contracts;
+using System.Diagnostics.Contracts;
 using System.Runtime.CompilerServices;
 
 namespace X10D.Math;
@@ -97,7 +97,7 @@ public static class UInt64Extensions
             case <= 3: return true;
         }
 
-        if (value % 2 == 0 || value % 3 == 0)
+        if ((value & 1) == 0 || value % 3 == 0)
         {
             return false;
         }