DES MOINES, Iowa — Dreams of riches inspired a flurry of ticket-buyers, sending this weekend’s Powerball jackpot surging to $800 million even faster than lottery officials expected.

Lottery officials say sales have been robust since no one won Wednesday’s estimated $500 million jackpot, and the prize could grow even more. It will be the biggest U.S. jackpot ever, beyond the previous record of a $656 million Mega Millions prize won in 2012 by players in Kansas, Illinois and Maryland.

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

Here are more details about the giant jackpot:

How did the jackpot get so large?

The jackpot for the twice-weekly game started at $40 million on Nov. 4 and has been growing ever since. Because the payout is based on sales, the prize has grown more quickly as people rush to buy tickets.

Payment options

A winner would have the option of being paid $800 million through annual payments over 29 years or opting for $496 million in cash.

The odds? Not good

The odds are one in 292.2 million, which means you’re really, really, really unlikely to win. To put those odds in perspective, they’re about the same as the chance of flipping a coin and getting heads 28 times in a row. But as lottery officials often note, you have no chance of winning if you don’t buy a ticket.

Pooling your money

Some players feel they improve their chance of winning by pooling their money with co-workers, with a promise to split the winnings. While that can increase the fun of playing, the odds of winning are so tiny that adding 50 or 100 chances doesn’t change much. Lottery officials recommend that if people pool their money, they put in writing how they plan to split the prize — since it’s easy for misunderstandings to crop up when hundreds of millions of dollars are at stake.

Lottery: Selling hope to the hopeless

• Maine Center for Public Interest reporting shows that lottery ticket sales go up when people lose their jobs.
• Part 2 of this series looks at Maine’s approach to marketing and advertising the Maine lottery.
• Part 3 looks at legislators who weigh the costs and benefits of Maine’s state-run lottery.
• Part 4 checks in with lawmakers for closer scrutiny of Maine’s $230 million-a-year state-run lottery.