KEY POINTS
  • The top prize has been growing since mid-October, when two tickets split a $502 million jackpot.
  • The chance of hitting the top prize is about one in 302.6 million.
  • If you beat those odds, there are some things you should do — and not do — right off the bat.

Winning $640 million wouldn't be a bad way to close out the year.

That's the Mega Millions jackpot amount for the next drawing, which is set for Friday night. The top prize has been growing since Oct. 14 when it was reset to $20 million after two tickets — sold in Florida and California — matched all six numbers to split a $502 million jackpot.