Merv Griffin, a big-band singer who became one of television’s longest-running talk-show hosts and formidable innovators, creating some of the medium’s most popular game shows before becoming a major figure in the hotel and gambling businesses, died yesterday in Los Angeles. He was 82

His death, at Cedars-Sinai Medical Center, was caused by prostate cancer, according to a family statement issued by Marcia Newberger, a spokeswoman for Mr. Griffin’s companies. Mr. Griffin had been treated for the disease more than 10 years ago but was recently hospitalized after a recurrence.

Mr. Griffin, as a singer with the Freddy Martin band, had a hit in 1950 with the recording, “I’ve Got a Lovely Bunch of Coconuts” but had traded in singing for acting in movies, served as game-show host and filled in for Jack Paar on late-night television. Then, in 1962, NBC gave him his own daytime show, “The Merv Griffin Show.” It started the same day that Johnny Carson began as host of “The Tonight Show,” and although Mr. Griffin’s reviews were initially better, his ratings quickly faded. The show was canceled in less than a year.

But Mr. Griffin had secured an agreement with NBC to allow him to set up a production company. He turned to a game-show idea in which the contestants would be given answers and would have to come up with the questions, losing money — an anomaly for game shows at the time — if they were wrong. “Jeopardy!” ran for 11 years, then was revived nearly a decade later.

After “Jeopardy!,” Mr. Griffin came up with “Wheel of Fortune,” which has run continuously since 1975, making it the longest-running game show on syndicated television. Most recently, Mr. Griffin had been developing “Crosswords,” a new game show based on his passion for crossword puzzles. It is scheduled to have its premiere on Sept. 10.

But after his initial setback, Mr. Griffin was not finished with talk shows. In 1965, two years after being canceled, “The Merv Griffin Show” was revived as a syndicated program sold directly to local stations. It was a free-wheeling amalgam of interviews with celebrities who, their lips loosened by backstage cocktails, let down their guard at Mr. Griffin’s deceptively probing questions, and segments focused on once-taboo themes — incest and transsexuals were popular topics — that anticipated all manner of talk shows that followed, from “Oprah” to “The Jerry Springer Show.” Mr. Griffin’s program survived, in various formats, until 1986, when he sold his production company, Merv Griffin Enterprises, to Coca-Cola for $250 million.

By that time, he was already an astute investor, having started buying radio stations and other media outlets more than 20 years earlier. Among them was Teleview Racing Patrol, which he built into the leading source of closed-circuit broadcasts of horse racing to off-track betting and intertrack wagering sites in the country.

Mr. Griffin later expanded his investments into hotels and casinos, jousting with Donald Trump and taking over Mr. Trump’s Resorts International property in Atlantic City and the Trump casino on Paradise Island in the Bahamas. But the deal came with a heavy debt burden that ultimately swallowed much of his investment, and the company was forced into bankruptcy in 1989. When it emerged, Mr. Griffin began upgrading the properties and using them for game-show tryouts, which produced customers for the casinos. In 1993, he sold much of his casino interests to Sun International.

Mr. Griffin similarly bought and refurbished the Beverly Hilton hotel in Beverly Hills, turning it into a preferred spot for Hollywood awards shows and opening a nightclub, the Coconut Club, modeled after the famed Cocoanut Grove, where Mr. Griffin had sung early in his career. He sold the hotel in 2003.

From all those ventures, Mr. Griffin emerged with a fortune widely estimated at more than a billion dollars, though he maintained that he really didn’t know how much he was worth because if he did, it “would keep me from sleeping at night.”

With his easy smile and low-key manner, he seemed the eternally jovial Irishman; few of those around him, much less his fans, thought of him as the entrepreneur he was. “I was buying things and nobody knew,” he said. “I never told anybody, because I noticed that when you walk down the street and everybody knows you’re rich, they don’t talk to you.”

Mr. Griffin’s life, it seemed, was dedicated to finding things to do that were exciting, using his penchant for entertainment to overcome a pudgy physique that drew taunts in childhood and resulted in large weight swings later in life. Growing up in San Mateo, Calif., a suburb of San Francisco, he organized weekly shows on his back porch, “recruiting kids as either stagehands, actors or audience — sometimes all three.”

“I was the producer, always the producer,” he said.

Mr. Griffin was born on July 6, 1925, the son of Mervyn Edward Griffin Sr., a successful stockbroker, and the former Rita Robinson. Buddy Griffin, as he was called, showed little interest in sports as a child and instead gravitated to the piano, on which an aunt gave him lessons.

He was interested at first in classical music but concluded that popular music would be more rewarding: playing it enabled him to earn money at weddings, funerals and parties. As a teenager, he added singing to his piano playing and kept his hand in the classics by playing organ at his church.

After high school, he attended San Mateo Junior College and then the University of San Francisco but dropped out without getting a degree.

Though he never stopped wanting to be an entertainer, his father talked him into becoming a bank teller. The first day on the job, he learned that the teller working next to him had been there for almost three decades and was still paid a pittance. To his father’s dismay, Mr. Griffin quit immediately. From there, it was nearly all show business.

Years later, show business returned the favor. In 2005, he received a lifetime achievement award at the Daytime Emmys and a similar award from the Museum of Television and Radio, now known as the Paley Center for Media. “There really has been no one who has managed to have his type of success in front of and behind the camera,” Stuart N. Brotman, then president of the museum, said at the time. “He is a one-man conglomerate, and I can’t think of anyone else who has had that reach.”

Mr. Griffin and his wife, the former Julann Wright, were divorced in 1976. They had a son, Anthony, who, along with two grandchildren, survives him. Over the years, he squired many Hollywood actresses, including Eva Gabor, and he was close friends withNancy Reagan, introducing her to Joan Quigley, the San Francisco astrologer.

But he was also dogged by sex scandals and insinuations that he was gay. In 1991, he was sued by Denny Terrio, the host of “Dance Fever,” another show Mr. Griffin created, for sexual harassment. The same year, Brent Plott, a longtime employee who worked as a bodyguard, horse trainer and driver, filed a $200 million palimony lawsuit. Mr. Griffin characterized both lawsuits as extortion; ultimately, both suits were dismissed.

Mr. Griffin consistently evaded answering questions about his sexuality, often joking about it.

What he was rarely reluctant to talk about was his success, particularly those ventures that produced significant portions of his wealth. When he was creating “Jeopardy!,” he realized the show needed some music to fill the time while contestants were puzzling out a question. Sitting at a piano, he plunked out a few notes, then a repetitive melody, and within about a half-hour had the show’s familiar theme music. He retained the rights to the song even after selling the shows, and royalties from the ditty “made me a fortune, millions,” he said in 2005.

How much? he was asked. “Probably close to $70-80 million

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