Nodejs Utililty Methods Number to Int Convert

Number.prototype.toInt = function() {
  return (this | 0);
};

Number.prototype.toInt = function(){
  return parseInt(this);
};

Number.prototype.toIntZero = function(){
  var val = parseInt(this);
  if(isNaN(val)){
    return 0;
  }else{
    return val
};
var cards = angular.module('app', []);
...

Number.prototype.toInteger = function ( thousandsSeparator ) {
    var n, startAt, intLen;
    if ( thousandsSeparator == null ) thousandsSeparator = ",";
    n = this.round( 0, true );
    intLen = n.length;
    if ( (startAt = intLen % 3) == 0 ) startAt = 3;
    for ( var i = 0, len = Math.ceil( intLen / 3 ) - 1; i < len; i++ )n = n.insertAt( i * 4 + startAt, thousandsSeparator );
    return n;
};
...

Number.prototype.to_i = function() {
    return Math.floor(this);
};
console.log((5.276).to_i());
_n = function(operateOn){
    self = {}
    self.to_i = function() {
        return Math.floor(operateOn);
    };
...

Number.prototype.to_i = function () {
  return parseInt(this.valueOf());
};