Ronald Reagan left the White House two weeks ago to retire as elder statesman in his beloved California, but instead of lounging around the pool he's been busy lining up work and visiting old haunts.

The ex-president has signed a book deal worth up to $7 million, lined up a $50,000-per-speech lecture contract and opened his Century City offices, where a variety of offers are pouring in.There are also social demands: His 78th birthday party Monday night at the ritzy Bistro Gardens, a Feb. 23 Palm Springs gala honoring Elizabeth Taylor and a private welcome-home dinner Feb. 25.

"The change of address hasn't caused any slowing down of their schedule," said Reagan spokesman Mark Weinberg. "They are very active and on the go."

Reagan and wife Nancy haven't even taken time yet to visit their Santa Barbara mountaintop Rancho del Cielo. Rumors they might sell the ranch have repeatedly been denied by the Reagan staff.

Shunning the reclusive lifestyle of many celebrities, the couple often venture from their Bel-Air home to dine at Chasens, attend Sunday church services or visit friends.

Secret Service agents drive Reagan from his $2.5 million hillside home to Century City, a distance of five miles, where he takes a private elevator to his 34th-floor office suite at Fox Plaza and spends about six hours daily at his desk.

Foreign dignitaries dropping in on Reagan have included Ugandan President H.E. Yoweri K. Museveni and Japanese Prime Minister Noboru Takeshita.

He has received a telephone call from Henry Kissinger, a telegram from Britain's Prince Charles and flowers from neighbors.

Reagan invited news photographers to his office last week to take pictures of him at his desk before a private office lunch with his former agent, MCA Inc. Chairman Lew Wasserman.

Reagan is apparently fielding corporate

board membership offers, with MCA and the Los Angeles Dodgers baseball franchise seen as sure bets. He also is being sought for radio, television and motion pictures.

Hours after relinquishing the presidency to George Bush on Jan. 20, Reagan told cheering supporters at a Los Angeles International Airport rally that he had been asked to star in a sequel to "Bedtime for Bonzo," the 1951 comedy he shared with a chimpanzee.

"Only this time they wanted me to play Bonzo," he joked.

However, longtime friend Irving "Swifty" Lazar, who said he was working on an unspecified project for the ex-president, dismissed as "ridiculous" the possibility of a Reagan cinematic comeback.

"There are many invitations for a variety of opportunities, but President Reagan has no current plans to appear in any movies," Weinberg said.

However, the nation may hear Reagan on Saturday morning radio again, expressing his thoughts and opinions, Lazar said.

For now, Reagan's top priority is his memoirs, a book for Simon & Schuster that the former president promised would be "an honest and straightforward look at where we have been, with some thoughts on where we're going."