javascript tousand seperator

JavaScript
function formatNumber(num) {
  return num.toString().replace(/(\d)(?=(\d{3})+(?!\d))/g, '$1,')
}

console.info(formatNumber(2665)) // 2,665
console.info(formatNumber(102665)) // 102,665
console.info(formatNumber(111102665)) // 111,102,665

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