How to convert an integer to an array in PHP?

Question

What would be the most simple way to convert an integer to an array of numbers?

Example:

2468 should result in array(2,4,6,8).

Answer 1

Example #2 Splitting a string into component characters

$str = 'string';
$chars = preg_split('//', $str, -1, PREG_SPLIT_NO_EMPTY);