// If the sum of cubes of individual digits of a number is equal to the number itslef  then it is called Armstrong Number.
<?php
if(isset($_POST['number']) && $_POST['number']!='')  
    {    
        
        $number = $_POST[ 'number' ];      // get the number entered by user
       
        $temp = $number;
        $sum  = 0;
       
        while($temp != 0 )
        {
            $remainder   = $temp % 10; //find reminder
            $sum         = $sum + ( $remainder * $remainder * $remainder ); 
            $temp        = $temp / 10; 
 
       }
        if( $number == $sum )
        {
            echo "$number is an Armstrong Number";
        }else
        {
            echo "$number is not an Armstrong Number";
        }
    }
?>