diff --git a/src/UniqueCodes.php b/src/UniqueCodes.php
index cb91f6e..8de2d85 100644
--- a/src/UniqueCodes.php
+++ b/src/UniqueCodes.php
@@ -224,7 +224,7 @@ protected function encodeNumber(int $number)
         $characters = $this->characters;
 
         for ($i = 0; $i < $this->length; $i++) {
-            $digit = intval($number % strlen($characters));
+            $digit = intval($number) % strlen($characters);
 
             $string = $characters[$digit] . $string;