<?php
function create_random_number($digits_quantity, $string = false, $zero = 1)   
     {   
         $random_number = 0;   
         $digits = 0;   
        
         while($digits < $digits_quantity)   
         {   
             $rand_max .= "9";   
             $digits++;   
         }   
            
         mt_srand((double) microtime() * 1000000);    
         $random_number = mt_rand($zero, intval($rand_max));   
        
         if($string)   
         {   
             if(strlen(strval($random_number)) < $digits_quantity)   
             {   
                 $zeros_quantity = $digits_quantity - strlen(strval($random_number));   
                 $digits = 0;   
                 while($digits < $zeros_quantity)   
                 {   
                     $str_zeros .= "0";   
                     $digits++;   
                 }   
                 $random_number = $str_zeros . $random_number;   
             }   
         }   
         return $random_number;   
     }
?>