Lottery officials say the prize is growing quickly Friday because so many people have been purchasing the $2 tickets. The jackpot has grown by an estimated $236 million since the last drawing on Wednesday.
The last jackpot was won on March 30, so it's been growing for about six weeks.
The $600 million jackpot is now the highest ever for Powerball, beating out the $587.5 million jackpot split between a Missouri couple and an Arizona woman last year.
The largest lottery jackpot in any game is a $656 million prize in the Mega Millions game in 2012.
Powerball is played in 43 states, the District of Columbia and the US Virgin Islands.
A single ticket costs $2, but your odds of winning the jackpot are pretty slim -- about one in 175 million.