Mega Millions jackpot numbers are ... 8-20-14-17-39 and 7.

The ultimate Christmas gift that could keep on giving and giving and giving. 

And the winning Mega Millions jackpot numbers are ... 8-20-14-17-39 and 7. 

If, by chance, you happen to hold a Mega Millions ticket with these six numbers, you've just won $636 million, the second-biggest lottery jackpot of all time. 

Take a deep breath. While the drawing was held at 11 p.m. ET Tuesday, lottery officials aren't expected to officially proclaim a winner — if there is one or more — until early Wednesday morning. 

Odds of winning: about 1 in 259 million. 

Tuesday's jackpot had rolled over 21 straight drawings since Oct. 4, worth a lump, sum, pre-tax payout worth $314.2 million. If there's no winner, Friday night's jackpot could surge past $825 million, eviscerating the $656 million record jackpot split by three winners in March 2012. 

And if it rolls over Friday? It could hit a whopping $1 billion by next Tuesday's Christmas Eve drawing, says Virginia lottery director Paula Otto, lead director for Mega Millions, played in 43 states, Washington, D.C. and the U.S. Virgin Islands. 

Ticket sales — the topic of TV, radio, social media and burgeoning office pools — surged in the hours leading up to the drawing, even though up to 75% of the possible number combinations were expected to be picked. 

 

"They're buying like crazy," Ahmed Karim, the owner of a New Brunswick 7-Eleven, told nj.com. 

"Even though the odds are against you, it's just the excitement of, 'Hey, I might wake up one day and be a millionaire,' " says Chris Scales, 31, of Nashville. The hot dog vendor says he earns about $35,000 a year "if I really hustle." 

The incredibly remote odds don't really sink in for people, says George Loewenstein, a professor of economics and psychology at Carnegie Mellon University who has researched the motives of lottery ticket buyers."People don't really understand probabilities at all," he says. "Once you have a bunch of zeroes, it doesn't matter how many you have — one in 10,000, one in a million or one in a billion. … People do understand the meaning of the word 'largest.' They overreact to one dimension and underreact to the other."  

Tuesday's drawing aside, Mega Millions jackpots are likely to continue swelling after lottery officials boosted their potential payouts.  

Originally, customers chose five numbers from 1-56 and one number from 1-46. The new structure has customers choosing five numbers from 1-75 and one number from 1-15. That sliced the odds of winning from 1 in 176 million to 1 in 259 million.  

Longtime lottery watcher Gail Howard says that with the odds of hitting the jackpot so small, ticket buyers should buy no more than one.  

"Your odds are not going to improve that much if you buy 1 ticket or 1,000,'' says Howard, author of Lottery Master Guide. "I also think you should pick your own numbers rather than let a (point of sale) computer do it."  

The current jackpot started at $12 million Oct. 4. By last week, it was up to $425 million, then $586 million on Monday before being raised to $636 million Tuesday morning.