This function, given a number, multiple, will tell you if it can be divided evenly into it.

PHP Code:
function is_multiple($number$multiple) {
     
$num $number $multiple;
     
$res strstr($num'.');
     if (
$res == false) {
          
$return true;
     } else {
          
$return false;
     }

     return 
$return;
}

//USAGE:

echo is_multiple(255);
//Will print: [I]true[/I]

echo is_multiple(65);
//Will print: [I]false[/I]