Timer limits

Hi,

I made a fully working timer, counting down, in js but I noticed that if timers time is more than 524288 it can't count down.

 var time1 : int; //for showing OnGUI() and stuff
 var time1f : float; //timer time
 var time1set : boolean;

  function Update()
  {
      if(time1set)
      {
         time1f-=Time.deltaTime;//if time1f>524288 timer don't work
         time1=time1f;
         if(time1<=0) EndTimer1();
      }
  }

any ideas?