how to format number in php to have zero before nu code example

Example 1: php number format

$num = 12345.6789;
echo number_format($num, 2, '.', '') //12345.67
echo number_format($num, 3, ',', '.') //12.345,678

Example 2: laravel number add 0 before

<?php
$num = 4;
$num_padded = sprintf("%02d", $num);
echo $num_padded; // returns 04
?>