Oh, to be 80 again. Or even 85.

For TV viewers who may have been more grossed out than engrossed in the recent "Growing Old in America," and for those who simply like watching an oldtimer have fun, CBS offers a George Burns special Friday night.

The birthday party, oddly titled "Kraft Salutes the George Burns 90th Birthday Special," features a slew of performers in comedy and musical segments. Offering a cameo appearance is another oldtimer, Ronald Reagan.

"The President?" said Burns. "He's just a kid. I'd send him out for a glass of water."

The special was to be taped Jan. 11 before a black-tie audience at the Beverly Theater in Los Angeles for airing Friday, three days before Burns' 90th birthday.

Burns' exposure as an active octogenarian, still producing movies and books and giving concerts, brings him a lot of mail from his peers. "They love what I'm doing," he said. "The secret to old age is not to retire. Don't fall in love with the bed. Of course, at our age, you can't do much there anyway."

If there is a secret to his longevity, Burns said, it may be his boundless love of show business and the energy he absorbs from his audiences.

"I still love show business as much as I did at 11 years of age," said Burns. "I did all kinds of acts. I felt sorry for audiences that didn't like me . . .

"The secret is to really fall in love with what you do. If you asked me to stand for an hour, I couldn't do it. But in front of an audience I can stand for two hours."

Looking, probably, way ahead, Burns even ponders death with a grin. "What would I want on my tombstone? I want to be standing there reading it.