Hmmmm. I'm guessing it's just a temp file. It could be that something else is putting nasty stuff in that temp file, but I don't think that 16493627018 is the source of your problem. It my be a sympton of the problem, though. Run a full virus scan with an up-to-date virus checker, and check the details if the virus checker finds anything.
Good luck.
-Joe Offer-