JSFiddle - React, Tailwind, and code Playground

by Vetrivel Samidurai

JavaScript

var x=123456524578;
x=x.toString();
var lastThree = x.substring(x.length-3);
var otherNumbers = x.substring(0,x.length-3);
if(otherNumbers != '')
    lastThree = ',' + lastThree;
var res = otherNumbers.replace(/\B(?=(\d{2})+(?!\d))/g, ",") + lastThree;

alert(res);