Breaking down the odds of winning Powerball's $700M jackpot

— -- The second-biggest Powerball drawing in U.S. history has reached $700 million, and that number could rise as more people buy tickets.

The winning numbers will be chosen tonight in Tallahassee, Florida. Some experts from Powerball gave "GMA" a little insight on the odds of taking home the grand prize.

If there are no winners tonight, the jackpot will jump to $1 billion, according to an official with DC Lottery.

Powerball officials have added numbers to the mix — which they said makes it easier for players to win smaller prizes. But more numbers have reduced the odds of winning the top prize to 1 in 292 million, from 1 in 175 million.

"More play happens at the higher level, so your odds of sharing it are greater at the greater jackpot levels," Powerball Chairman Charlie McIntyre told ABC News.

There has not been a jackpot-winning Powerball ticket since June 14, when it was $40 million.

Powerball officials told ABC News they expect to sell 170 million tickets between last Saturday and tonight's drawing.

Buying more tickets may seem like the secret to success, but McIntyre reiterated that is not necessarily the case.

"Your odds are just as good as anyone else," he said. "I've paid winners who bought one ticket. I've paid winners who bought 100 tickets. So it doesn't matter — you just have to have one ticket, at least."

"It's a completely random event," he added.

McIntyre also said luck can strike anywhere. "I've paid them from stores that sold 10 tickets in a day ... and millions in a year, so it's completely random."

Tracey Cohen, the executive director of the DC Lottery, told ABC News that players should remember one very important detail when they purchase a ticket.

"Immediately sign the back of it," she said. "If you are in a group pool, make copies of the ticket, decide who will sign it and what will happen if you have a winning ticket."

Even if no one wins the jackpot, prizes ranging from $4 to $1 million are still a possibility, Cohen said.

"There's a 1 in 38.2 chance that you could win something," she said.

Experts suggest that players use the full range of numbers available and not limit their chances by playing just numbers such as birthdays, since months have no more than 31 days and Powerball numbers go up to 69.

If there is a winner, he or she could choose an annuity to receive 30 payments over 29 years or take a lump sum, which would be $443.3 million at the current jackpot, according to Powerball.

The biggest Powerball jackpot was $1.6 billion in January 2016. People in California, Florida and Tennessee split the prize.

Powerball is played in 44 states, the District of Columbia, Puerto Rico and the U.S. Virgin Islands.