The Mega Millions jackpot is at a world record \$640 million. But before you start thinking about what you're going to do with all of that cash - there are some basic things everyone with a ticket needs to know, especially if you're lucky enough to be holding the winning numbers.

When are the drawings held?

The Mega Millions drawing will be held Friday from Atlanta at 11:00 p.m. Eastern Time, 10:00 p.m. Central Time, 8:00 p.m. Pacific Time.

What's the latest I can buy a Mega Millions ticket?

If you're a last minute kind of person - even with more than a half-a-billion on the line - not to worry. You can buy tickets up to 15 minutes before the drawing. (10:45 p.m. Eastern Time, 9:45 p.m. Central Time, 7:45 p.m. Pacific Time) Except if you live in Maine, New Hampshire and Vermont, where 9:50 p.m. is the deadline.

Where can I play Mega Millions?

You can buy Mega Millions tickets from lottery retailers/agents in 42 states plus the District of Columbia and the U. S. Virgin Islands; a total of 44 jurisdictions. The eight states that do not have Mega Millions drawings are Nevada, Utah, Wyoming, Mississippi, Alabama, Florida, Alaska, and Hawaii.

What are the odds of winning?

The math is clear: The more tickets you buy, the better your chances of winning. So, if you buy 10 tickets filled out 10 different ways, your odds of winning the jackpot 10 in 176 million.

Mike Catalano, chairman of the mathematics department at Dakota Wesleyan University in Mitchell, S.D., said he covers the odds of winning in lottery games with his students to show them just how unlikely it is to win big.

You are about 50 times more likely to get struck by lightning than winning the lottery, based on the 90 people a year getting struck by lightning. Based on other U.S. averages, you're about 8,000 times more likely to be murdered than to win the lottery, and about 20,000 times more likely to die in a car crash than hit the lucky numbers, Catalano said.

What could I do with all of that money?

Assuming the jackpot were \$540 million, that means for one winner the lump sum would be \$389 million, and the final estimate after state and federal taxes is around \$253 million.

To put \$253 million into context, you could:

-- pay off 1/10,000 of the U.S. debt;

-- [on average] feed a family of four for 22,381 years OR feed 22,381 families of four for one year;

-- buy 1,265 seats/trips to outer space aboard Virgin Galactic;

-- start a company and pay 10 employees \$100,000 for 253 years;

-- buy Michael Jackson's estate [\$23.9 Million], Britney Spears' mansion [\$2.9 million], Madonna's Beverly Hills mansion [\$28 million], Jerry Seinfeld's Colorado estate [\$18 million] and Michael Jordan's Chicago-area estate [\$29 million] AND STILL have \$150 million remaining.

every day:

-- to burn through it in a year, you'd need to spend \$693,150 per day

-- to burn through it in 80 years, you'd need to spend \$8,658 per day

If you win - should you take an annuity or lump sum?

Bottom line: Get a financial adviser, accountant and lawyer.

Mega Millions does not have the exact number of lottery winners that have taken a lump sum versus annuity payments, but a spokesperson for Mega Millions says most take the cash in a lump sum.

According to Mega Millions, a jackpot winner can choose the annuity option of annual payments over a 26-year-period or just a lump sum of cash.

Did you know? If you were in a high-yield savings account, yielding 0.8%, you'd finish the year with \$255,038,930. That's more than \$2 million in interest even with the current extremely low interest rates.

What happens if there are multiple winners?

With a jackpot this large, experts say, there also is a greater chance of multiple winners. If you have to share the jackpot with even one other winner, you've lost \$30 million.

What fuels lottery mania?

It's hope.

A 2008 study from Journal of Risk and Uncertainty explained that households earning under \$13,000 per year spend about 9 percent of their income on lottery tickets on average, or around \$645 a year.

But for some, the chance — however small — of instantaneous, enormous wealth is leading to long lines at convenience stores in 42 states and Washington, D.C., where Mega Millions tickets are sold.  It's why David Kramer, a lawyer in Lincoln, bought a Mega Millions ticket Thursday.

"To me, the value of the lottery ticket isn't the realistic opportunity to win," he said. "It's the fact that for three days, the daydreaming time about what I would do if I won is great entertainment and, frankly, a very nice release from a normal day."

Some final words of wisdom...

Lottery officials are happy to have Friday's record Mega Millions jackpot fueling ticket sales, but even they caution against spending large amounts of money per person in the hopes of striking it rich.

"We certainly know we get more pool play ... people coming in making very large purchases for a group," said Chuck Strutt, executive director of the Urbandale, Iowa-based Multi-State Lottery Association that oversees the Mega Millions, Powerball and other lotteries. "When people ask me, I just tell them that the odds of a lottery game make it a game of fate. Just buy a ticket, sit back and see if fate points a finger at you for that day."

Contains material from The Associated Press.