diff --git a/src/main/java/net/agkn/hll/serialization/BigEndianAscendingWordDeserializer.java b/src/main/java/net/agkn/hll/serialization/BigEndianAscendingWordDeserializer.java
index 5bbaa6a..6b04771 100644
--- a/src/main/java/net/agkn/hll/serialization/BigEndianAscendingWordDeserializer.java
+++ b/src/main/java/net/agkn/hll/serialization/BigEndianAscendingWordDeserializer.java
@@ -100,7 +100,7 @@ private long readWord(final int position) {
         }
 
         // First bit of the word
-        final long firstBitIndex = (position * wordLength);
+        final long firstBitIndex = ((long)position) * ((long)wordLength);
         final int firstByteIndex = (bytePadding + (int)(firstBitIndex / BITS_PER_BYTE));
         final int firstByteSkipBits = (int)(firstBitIndex % BITS_PER_BYTE);
 
diff --git a/src/main/java/net/agkn/hll/serialization/BigEndianAscendingWordSerializer.java b/src/main/java/net/agkn/hll/serialization/BigEndianAscendingWordSerializer.java
index 3ad7ce1..367e677 100644
--- a/src/main/java/net/agkn/hll/serialization/BigEndianAscendingWordSerializer.java
+++ b/src/main/java/net/agkn/hll/serialization/BigEndianAscendingWordSerializer.java
@@ -86,7 +86,7 @@ public BigEndianAscendingWordSerializer(final int wordLength, final int wordCoun
         this.wordLength = wordLength;
         this.wordCount = wordCount;
 
-        final long bitsRequired = (wordLength * wordCount);
+        final long bitsRequired = ((long)wordLength) * ((long)wordCount);
         final boolean leftoverBits = ((bitsRequired % BITS_PER_BYTE) != 0);
         final int bytesRequired = (int)(bitsRequired / BITS_PER_BYTE) + (leftoverBits ? 1 : 0) + bytePadding;
         bytes = new byte[bytesRequired];