diff --git a/src/FreeDSx/Asn1/Asn1.php b/src/FreeDSx/Asn1/Asn1.php
index 7bdf9db..9c4f684 100644
--- a/src/FreeDSx/Asn1/Asn1.php
+++ b/src/FreeDSx/Asn1/Asn1.php
@@ -67,10 +67,10 @@ public static function sequenceOf(AbstractType ...$types): SequenceOfType
     }
 
     /**
-     * @param int $int
+     * @param int|string $int
      * @return IntegerType
      */
-    public static function integer(int $int): IntegerType
+    public static function integer($int): IntegerType
     {
         return new IntegerType($int);
     }
diff --git a/tests/spec/FreeDSx/Asn1/Asn1Spec.php b/tests/spec/FreeDSx/Asn1/Asn1Spec.php
index c0c5dfd..64acdea 100644
--- a/tests/spec/FreeDSx/Asn1/Asn1Spec.php
+++ b/tests/spec/FreeDSx/Asn1/Asn1Spec.php
@@ -66,6 +66,12 @@ public function it_should_construct_an_integer_type()
         $this::integer(1)->shouldBeLike(new IntegerType(1));
     }
 
+    public function it_should_construct_an_integer_type_from_a_numeric_string(): void
+    {
+        $this::integer('99999999999999999')
+            ->shouldBeLike(new IntegerType('99999999999999999'));
+    }
+
     public function it_should_construct_an_enumerated_type()
     {
         $this::enumerated(1)->shouldBeLike(new EnumeratedType(1));