Your dream of buying 654 castles or maybe 171 private islands could become reality after tonight's $720 million Mega Millions jackpot drawing.

The six coveted numbers will be plucked at 11 p.m. ET Friday. If you hit the jackpot but don't want to wait 29 years to collect all your millions, the cash value option is $369.6 million.

The $720 million jackpot is among the biggest in Mega Millions history. The jackpot has jumped past the $700 million mark only four previous times, the lottery said.

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But don't start shopping for new houses yet. The odds of hitting the Mega Millions jackpot has gotten worse in recent years -- from about 1 in 258 million to about 1 in about 302 million.

That's because lottery officials have added more balls and Mega Balls into the mix -- meaning there's a wider array of number combinations for players to pick.

While that makes it harder to score the jackpot, it also helps jackpots snowball to astronomical amounts when no one wins. And lottery officials have said more people can become millionaires by winning secondary prizes.

A lucky player in California hit the $1.08 billion Powerball jackpot