Transform ms in days, hours, minutes and seconds.

ms_to_days.js

// example 1: format "Days" : days, "Hours" : hours, "Minutes" : minutes, "Seconds" : seconds
millisToTime = function(ms) {
  x = ms / 1000;
  seconds = Math.round(x % 60);
  x /= 60;
  minutes = Math.round(x % 60);
  x /= 60;
  hours = Math.round(x % 24);
  x /= 24;
  days = Math.round(x);

  return {"Days" : days, "Hours" : hours, "Minutes" : minutes, "Seconds" : seconds};
}

// example 2: format 00:00:00 => day:hour:minute
function dhm(ms){
  var cDay = 24 * 60 * 60 * 1000
    , cHour = 60 * 60 * 1000
    , day = Math.floor(ms / cDay)
    , hour = '0' + Math.floor( (ms - day * cDay) / cHour)
    , minute = '0' + Math.round( (ms - day * cDay - hour * cHour) / 60000);
    
  return [day, hour.substr(-2), minute.substr(-2)].join(':');
}