diff --git a/phpseclib/Math/BigInteger/Engines/Engine.php b/phpseclib/Math/BigInteger/Engines/Engine.php
index 2b00bc37..abdf3b47 100644
--- a/phpseclib/Math/BigInteger/Engines/Engine.php
+++ b/phpseclib/Math/BigInteger/Engines/Engine.php
@@ -644,6 +644,11 @@ abstract class Engine implements \JsonSerializable
             return $this->normalize($temp->powModInner($e, $n));
         }
 
+        if ($this->compare($n) > 0) {
+            list(, $temp) = $this->divide($n);
+            return $temp->powModInner($e, $n);
+        }
+
         return $this->powModInner($e, $n);
     }