// Javascript has a number formatter (part of the Internationalization API).
const number = 123456.789;
// another example
console.log(new Intl.NumberFormat('ja-JP', {
style: 'currency',
currency: 'BWP',
}).format(number));
// MORE INFO -> https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/NumberFormat