Las Vegas- Hotel heiress Nicky Hilton beat big sister Paris to the altar, opting for a quickie predawn wedding in Las Vegas yesterday to Manhattan money manager Todd Andrew Meister.

The 20-year-old bride and 33-year-old groom exchanged vows in a 3 a.m. ceremony at the Las Vegas Wedding Bureau and Vegas Chapel.

“They came in saying they wanted the best,” said Shirley Harvey, the chapel’s president and co-owner. “They seemed pleased and happy when they left.”

Meister is the son of Robert Meister, vice chairman of Aon Group Inc., a global insurance brokerage firm. His mother, Wendy Meister, died of cancer at age 57 in 2001. Known as a playboy, Meister, who owns a private plane and homes on Park Ave. and in Palm Beach, Fla., has dated a string of socialites.

He began dating Hilton last year after she dumped ex-MTV veejay Bryan McFayden.

“He’s a longtime friend of the family,” said Couri Hay, a close friend of Nicky’s parents, Kathy and Rick Hilton. “I’ve seen him at Christmases and birthdays in Southampton, New York and Aspen. I know that Kathy and Rick really like him,” Hay told the Daily News.

Hay insisted the wedding was “not an unreasonable Britney Spears moment,” referring to the pop singer’s quickie Vegas marriage in January that lasted 55 hours. “It was a quiet friendship that has apparently blossomed into love and then marriage,” Hay said.

Harvey refused to give details of the couple’s wedding but she said they demanded that digital cameras, available to broadcast the wedding on the Internet, be turned off. Maybe Nicky is learning from her big sister’s mistakes: Paris was embroiled in a scandal last year when a private porn video of her was leaked over the Internet.

Sources said Paris, 23, was on hand for her little sister’s wedding. Other guests included actress Bijou Phillips and comedian Jeff Beacher.

Nicky Hilton, a part-time actress and handbag designer, flew into Vegas on Friday night to attend a weekend casino party sponsored by Stuff magazine. She arrived in the desert gambling mecca with Paris and her sidekick Nicole Richie, Phillips and actress Tara Reid.

The Hiltons and Meister attended the Stuff magazine soiree at the Palms Hotel & Casino with MTV’s Vanessa Minnillo, actress Lindsay Lohan and her boyfriend, Wilmer Valderrama, ‘NSync’s Lance Bass and Dominique Swain.

At Saturday night’s wild late-night pool party, Phillips was photographed throwing pillows at swimmers.

Harvey said that just before midnight, a representative of the bride called the chapel to reserve some time at the altar.

“We were getting close to closing, so when we got their call we just thought they wanted it private so we stayed open for them,” said Harvey, adding that Hilton and Meister were among 30 couples to get married at the chapel yesterday.