The comic, who disclosed last year that he was battling Parkinson's disease, died at his home in Los Angeles on Tuesday evening after suffering a heart attack, publicist Jeff Abraham said.
"Richard and I were born three days apart in the same hospital and for most of my life he's been like a brother to me," David said in a written statement. "He had that rare combination of being the funniest person and also the sweetest. But today he made me sob and for that I'll never forgive him."
"His wife, Joyce Lapinsky, thanks everyone for all the love, friendship and support and asks for privacy at this time," Abraham said in a written statement.
Brooklyn-born Lewis began performing stand-up comedy in the early 1970s while working a day job in advertising and by the end of the decade had risen to the forefront of his generation of comedians.
He was a regular on late-night talk shows through the 1980s and starred alongside Jamie Lee Curtis on the ABC TV comedy "Anything But Love." He made several film appearances in the 1990s, most notably in "Robin Hood: Men in Tights."
In later years he was best known for playing a version of himself as Larry David's friend on "Curb Your Enthusiasm," in which the two men bickered relentlessly.
