Random Number Generator

/**
 * Generates a random number of a fixed number of digits.
 * 
 * The use of STR_PAD_LEFT allows the result to ALWAYS be the given number of
 * digits, using leading zeros in instances where the number is less than the
 * number of digits (such as 000001 or 002345 ).
 */

// The number of digits.
$x = 6;

// Generate a random $x digit number.
$number = str_pad( rand( 0, pow( 10, $x )-1 ), $x, '0', STR_PAD_LEFT );