diff --git a/src/Common/src/System/Collections/HashHelpers.cs b/src/Common/src/System/Collections/HashHelpers.cs
index 4fc621db290d..b19505644f7d 100644
--- a/src/Common/src/System/Collections/HashHelpers.cs
+++ b/src/Common/src/System/Collections/HashHelpers.cs
@@ -23,8 +23,6 @@ namespace System.Collections
 {
     internal static class HashHelpers
     {
-        private const Int32 HashPrime = 101;
-
         // Table of prime numbers to use as hash table sizes. 
         // A typical resize algorithm would pick the smallest prime number in this array
         // that is larger than twice the previous capacity. 
@@ -41,23 +39,12 @@ internal static class HashHelpers
             1103, 1327, 1597, 1931, 2333, 2801, 3371, 4049, 4861, 5839, 7013, 8419, 10103, 12143, 14591,
             17519, 21023, 25229, 30293, 36353, 43627, 52361, 62851, 75431, 90523, 108631, 130363, 156437,
             187751, 225307, 270371, 324449, 389357, 467237, 560689, 672827, 807403, 968897, 1162687, 1395263,
-            1674319, 2009191, 2411033, 2893249, 3471899, 4166287, 4999559, 5999471, 7199369 };
-
-        public static bool IsPrime(int candidate)
-        {
-            if ((candidate & 1) != 0)
-            {
-                int limit = (int)Math.Sqrt(candidate);
-                for (int divisor = 3; divisor <= limit; divisor += 2)
-                {
-                    if ((candidate % divisor) == 0)
-                        return false;
-                }
-                return true;
-            }
-            return (candidate == 2);
-        }
-
+            1674319, 2009191, 2411033, 2893249, 3471899, 4166287, 4999559, 5999471, 7199369, 8639249, 10367101,
+            12440537, 14928671, 17914409, 21497293, 25796759, 30956117, 37147349, 44576837, 53492207, 64190669,
+            77028803, 92434613, 110921543, 133105859, 159727031, 191672443, 230006941, 276008387, 331210079,
+            397452101, 476942527, 572331049, 686797261, 824156741, 988988137, 1186785773, 1424142949, 1708971541,
+            2050765853, MaxPrimeArrayLength };
+        
         public static int GetPrime(int min)
         {
             if (min < 0)
@@ -70,13 +57,6 @@ public static int GetPrime(int min)
                 if (prime >= min) return prime;
             }
 
-            //outside of our predefined table. 
-            //compute the hard way. 
-            for (int i = (min | 1); i < Int32.MaxValue; i += 2)
-            {
-                if (IsPrime(i) && ((i - 1) % HashPrime != 0))
-                    return i;
-            }
             return min;
         }
 
diff --git a/src/System.Collections/src/System/Collections/Generic/HashSet.cs b/src/System.Collections/src/System/Collections/Generic/HashSet.cs
index c772bfa45da4..5828dd2e063f 100644
--- a/src/System.Collections/src/System/Collections/Generic/HashSet.cs
+++ b/src/System.Collections/src/System/Collections/Generic/HashSet.cs
@@ -1013,8 +1013,6 @@ private void IncreaseCapacity()
         /// </summary>
         private void SetCapacity(int newSize, bool forceNewHashCodes)
         {
-            Debug.Assert(HashHelpers.IsPrime(newSize), "New size is not prime!");
-
             Debug.Assert(_buckets != null, "SetCapacity called on a set with no elements");
 
             Slot[] newSlots = new Slot[newSize];