By Todd Northrop

A rush of ticket sales for the half-billion-dollar Mega Millions jackpot has prompted lottery officials to revise their estimate for the Friday night drawing to $521 million.

The all-important lump-sum cash value is now estimated to be a staggering $317.2 million.

Friday's drawing will be the 24th since Mega Millions had a winner. The current jackpot run-up started on Jan. 9 as a $40 million grand prize.

According to the Maryland Lottery, if nobody wins the Friday jackpot, the jackpot for Tuesday, April 3 will be $612 million, making it the 3rd-largest in Mega Millions history and the 5th-largest in U.S. jackpot history. (See the top-25 cash and annuity jackpots below.)

Lottery players seeking to check the winning numbers Friday night are urged to use USA Mega (www.usamega.com). State lottery Web sites are normally sluggish or brought to a standstill during busy periods, while USA Mega normally remains responsive.

Mega Millions drawing results will be posted immediately after the 11:00 pm drawing at USA Mega. The number of winners and new jackpot will be announced after all participating states have reported their data, which normally occurs within a few hours after the drawing.

Tickets will remain on sale typically until 10:45 pm Eastern Time on Friday, although players should check with a lottery retailer in their state for the exact sales cutoff time. (Every state is different.)  Players are strongly advised not to wait until the last minute.

The odds of winning the jackpot are approximately 1 in 302 million. The odds of winning any of the Mega Millions prizes are 1 in 24.

Mega Millions tickets cost $2 each. For an extra $1 per ticket players can purchase the Megaplier option, which multiplies any non-jackpot won by up to 5 times, depending on the Megaplier number drawn that evening.

The only state that does not offer the Megaplier is California, because state law banning fixed lottery prize amounts is not compatible with the fixed nature of the Megaplier payouts.

Lottery players can see an after-tax analysis of the current Mega Millions jackpot by visiting USA Mega's Jackpot Analysis page.

Mega Millions features nine different prize levels, ranging from $2 all the way up to the jackpot. Players can win even if they just match one number — the Mega Ball number.

Top 25 United States lottery jackpots of all time

Friday's Mega Millions jackpot currently stands as the 7th-largest lottery jackpot of all time in the United States.

1. Powerball: $1.5864 billion, Jan. 13, 2016 - California, Florida, Tennessee
2. Powerball: $758.7 million, Aug. 23, 2017 - Massachusetts
3. Mega Millions: $656 million, Mar. 30, 2012 - Illinois, Kansas, Maryland
4. Mega Millions: $636 million, Dec. 17, 2013 - California, Georgia
5. Powerball: $590.5 million, May 18, 2013 - Florida
6. Powerball: $587.5 million, Nov. 28, 2012 - Arizona, Missouri
7. Powerball: $564.1 million, Feb. 11, 2015 - North Carolina, Puerto Rico, Texas
8. Powerball: $559.7 million, Jan. 6, 2018 - New Hampshire
9. Mega Millions: $536 million, Jul. 8, 2016 - Indiana
10. Mega Millions: $521 million, Mar. 30, 2018 - Preliminary estimate, not won yet
11. Powerball: $487 million, Jul. 30, 2016 - New Hampshire
12. Powerball: $456.7 million, Mar. 17, 2018 - Pennsylvania
13. Mega Millions: $451 million, Jan. 5, 2018 - Florida
14. Powerball: $448.4 million, Aug. 7, 2013 - Minnesota, New Jersey (2)
15. Powerball: $447.8 million, Jun. 10, 2017 - California
16. Powerball: $435.3 million, Feb. 22, 2017 - Indiana
17. Powerball: $429.6 million, May 7, 2016 - New Jersey
18. Powerball: $425.3 million, Feb. 19, 2014 - California
19. Powerball: $420.9 million, Nov. 26, 2016 - Tennessee
20. Mega Millions: $414 million, Mar. 18, 2014 - Florida, Maryland
21. Powerball: $399.4 million, Sep. 18, 2013 - South Carolina
22. Mega Millions: $393 million, Aug. 11, 2017 - Illinois
23. Mega Millions: $390 million, Mar. 6, 2007 - Georgia, New Jersey
24. Mega Millions: $380 million, Jan. 4, 2011 - Idaho, Washington
25. Powerball: $365 million, Feb. 18, 2006 - Nebraska

For those keeping score, the number of jackpots in the top 25, by lottery game, are:

• Powerball: 16
• Mega Millions: 9

Top 25 cash value jackpots

Since many lottery winners collect their winnings in cash, the lump-sum payout is an important measure of what a winning ticket could be worth.

Looking at the cash value, the upcoming Mega Millions jackpot ranks as the 11th-largest cash value in U.S. history.

1. Powerball: $983.5 million cash, Jan. 13, 2016 ($1.5864 billion annuity) - California, Florida, Tennessee
2. Powerball: $480.5 million cash, Aug. 23, 2017 ($758.7 million annuity) - Massachusetts
3. Mega Millions: $471 million cash, Mar. 30, 2012 ($656 million annuity) - Illinois, Kansas, Maryland
4. Powerball: $384.7 million cash, Nov. 28, 2012 ($587.5 million annuity) - Arizona, Missouri
5. Powerball: $381.1 million cash, Feb. 11, 2015 ($564.1 million annuity) - North Carolina, Puerto Rico, Texas
6. Mega Millions: $378 million cash, Jul. 8, 2016 ($536 million annuity) - Indiana
7. Powerball: $370.9 million cash, May 18, 2013 ($590.5 million annuity) - Florida
8. Powerball: $352 million cash, Jan. 6, 2018 ($559.7 million annuity) - New Hampshire
9. Mega Millions: $347.6 million cash, Dec. 17, 2013 ($636 million annuity) - California, Georgia
10. Powerball: $336.8 million cash, Jul. 30, 2016 ($487 million annuity) - New Hampshire
11. Mega Millions: $317.2 million cash, Mar. 30, 2018 ($521 million annuity) - Preliminary estimate, not won yet
12. Powerball: $284 million cash, May 7, 2016 ($429.6 million annuity) - New Jersey
13. Mega Millions: $281.9 million cash, Jan. 5, 2018 ($451 million annuity) - Florida
14. Powerball: $279.1 million cash, Jun. 10, 2017 ($447.8 million annuity) - California
15. Powerball: $273.9 million cash, Mar. 17, 2018 ($456.7 million annuity) - Pennsylvania
16. Powerball: $263.5 million cash, Feb. 22, 2017 ($435.3 million annuity) - Indiana
17. Powerball: $258.2 million cash, Aug. 7, 2013 ($448.4 million annuity) - Minnesota, New Jersey (2)
18. Powerball: $254.7 million cash, Nov. 26, 2016 ($420.9 million annuity) - Tennessee
19. Mega Millions: $246.5 million cash, Aug. 11, 2017 ($393 million annuity) - Illinois
20. Mega Millions: $240 million cash, Jan. 4, 2011 ($380 million annuity) - Idaho, Washington
21. Mega Millions: $233.1 million cash, Mar. 6, 2007 ($390 million annuity) - Georgia, New Jersey
22. Mega Millions: $230.9 million cash, Mar. 18, 2014 ($414 million annuity) - Florida, Maryland
23. Powerball: $227.8 million cash, Feb. 19, 2014 ($425.3 million annuity) - California
24. Powerball: $224.7 million cash, Aug. 15, 2012 ($337 million annuity) - Michigan
25. Powerball: $223.3 million cash, Sep. 18, 2013 ($399.4 million annuity) - South Carolina

The number of cash value jackpots in the top 25, by lottery game, are:

• Powerball: 16
• Mega Millions: 9