// An Armstrong number of three digits is an integer that the sum
// of the cubes of its digits is equal to the number itself
// 371 is an Armstrong number: 3**3 + 7**3 + 1**3 = 371
$n = 371;
$sum = 0;
$tmp = $n;
while ($n != 0)
{
$reminder = $n % 10;
$n = (int)($n / 10);
$sum = $sum + ($reminder * $reminder * $reminder);
}
if ($sum == $tmp)
echo $tmp . " is an Armstrong number <br />";
else
echo $tmp . " is not an Armstrong number <br />";
/*
run:
371 is an Armstrong number
*/