LOS ANGELES (CBS) — The Mega Millions jackpot for Friday night has swelled to $312 million, the sixth-largest jackpot in the lottery's nearly 15-year history.

A ticket with all six numbers has not been sold since the Feb. 1 draw, 14 draws ago.

Tickets will be sold until 7:45 p.m. The draw will be held just before 8 p.m.

The odds of matching all five numbers and the Mega number are 1 in 175,711,536, according to the Mega Millions Web site.

The Mega Millions game is now played in 41 states and the District of Columbia.

Buying tickets at a store where winning tickets have been sold in the past will not increase a purchaser's chance of winning a jackpot, according to USC mathematics professor Ken Alexander.

"The chance that a given place will sell a winning lottery ticket is just related to how many tickets they sell," Alexander said.