how to format to 2 digit decimal in php code example

Example 1: php float 2 decimais

$foo = "105";
echo number_format((float)$foo, 2, '.', '');

Example 2: number format php

<?php
echo number_format("1000000")."<br>";
echo number_format("1000000",2)."<br>";
echo number_format("1000000",2,",",".");
?>