Javascript Number bin32()

/**/*from   w  w w.  j  av  a  2  s . c  om*/
 * @param {number} n - a positive integer
 * @return {number} - a positive integer
 */

Number.prototype.bin32 = function () {
 var result = this.toString(2);
 while (result.length < 32) {
  result = '0' + result;
 }
 return result;
}

var reverseBits = function (n) {
 return parseInt(n.bin32().split('').reverse().join(''), 2);
};