php two decimal places

return number_format((float)$number, 2, '.', '');

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

echo round(520.34345, 2);   // 520.34
echo round(520.3, 2);       // 520.3
echo round(520, 2);         // 520

$number = 1234545454; 
echo  $english_format_number = number_format($number, 2);