Working with big integer values in Laminas

Code
<?php

use Laminas\Math\BigInteger\BigInteger;

$i 100000000000000000000 1;
dump($i);

$bcmath BigInteger::factory('Gmp');
$i $bcmath->add('100000000000000000000''1');
dump($i);
Result
^ 1.0E+20

^ "100000000000000000001"
Used Versions
PHP 8.0, Laminas MVC 3.2, Symfony 5.2, Laravel 8.28, PHPUnit 9.5, Doctrine ORM 2.8