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// Only Int value, not Float
function commaSeparatedNumber(n) {
  var ar = n.toString().split('').reverse()

  ret = []
  for(var i = 0; i < ar.length; i++ ) {
    if(i > 0 && i % 3 === 0) { ret.push(',') }
    ret.push(ar[i])
  }
  
  return ret.reverse().join('')
}

$(function() {
  var largeNumber = 1000
  var n = largeNumber * largeNumber
  
  $('#out').html(commaSeparatedNumber(n))
})
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