format string to right.... format

[JoelJ]

Hi.
I have a string, $number, that i want to look like this (# = a number) "### ##" no mather what the userinput looks like.
thankful for answers/
joel

[devinemke]

if all you want to do is add a space between digits 3 and 4:

$number = '12345';
$number_left = substr ($number, 0, 3);
$number_right = substr ($number, -2);
$new_number = $number_left . ' ' . $number_right;
echo $new_number;