He bought two lotto tickets in his life and won $724m

Richard Wahl speaks during a news conference introducing him as the US$533 million Mega Millions jackpot winner at the New Jersey Lottery headquarters. Photo/AP

Richard Wahl bought only two Mega Millions lottery tickets in his 47 years, and one was a dud.

The other, purchased as an afterthought along with a Diet Coke during a stop for gas in Riverdale, New Jersey, netted him a US$533 million ($724.11m) prize, the fourth largest in the game's history and one of the 10 largest jackpots ever.

"It's not only life-changing money for me, but I want it to be life-changing money for others," he told reporters on Friday.

"Family, friends, people in need. So we're going to try to do some good things with it."

Wahl, a production manager at a food-service company who only moved in July to New Jersey from Michigan with his family, said he would use a financial team to help decide how to dole the money out between his family, friends and others.

In particular, he is thinking of his mother, who lives on a reduced income, and the family of his wife, in Mexico.

But he's also got some ideas for himself, like a vacation, rebuilding a 1960s Corvette and, hopefully retiring from his job.

"We're not the type that's going to run out and spend all the money," Wahl said, according to ABC. "We're a humble family. We'll keep our roots."

Wahl and his family opted to take the payment in a lump sum of US$324 million, or about US$175 million after taxes.

He told reporters on Friday about the moment when he learned he was the winner, during the March 30 drawing.

He said he told his wife he was going to check the numbers and joked that "If I win you're going to hear a huge scream, we're leaving on vacation, we're going to retire," he said.

He noticed that the first five numbers he had matched those that were drawn. The sixth number, and last, was a 1 - a perfect match.

"I went over and looked at that one," Wahl said, pausing briefly with tears in his eyes. "I can tell you, it didn't sink in. It was truly amazing."

He didn't yell or scream, as some of the people in his house were sleeping. Instead he went to tell his wife.

"I said 'Baby, we get to go on vacation,' " Wahl said. "She said, 'What are you talking about, don't be an idiot.' I said, 'No seriously, we hit it.' "