In December, he developed pneumonia after undergoing heart-bypass surgery.

Randall achieved fame as the fastidious Unger, who shared an apartment with fellow divorcee Oscar Madison, who was played by Jack Klugman. Where Unger was obsessed with cleanliness and order, Madison was an unrepentant slob who thrived on messiness. The show ran from 1970 to 1975 on ABC, and earned Randall an Emmy Award.

In recent commentary about the program, some writers have claimed Felix was a prototypical metrosexual, long before the term had been invented. In the run-up to the recent finale of Frasier, many TV critics named Unger as the TV antecedent of Frasier and Niles Crane.

The show was based on the 1968 movie starring Jack Lemmon (in the Felix role) and Walter Matthau (as Oscar). The movie was in turn inspired by the Neil Simon stage production, which was a hit on Broadway in 1965.

The TV show inspired the 1982 series The New Odd Couple, which had black actors in the title roles, as well as an animated series, The Oddball Couple, which featured a neat cat and a sloppy dog.

Randall also worked on the stage and in movies. On the big screen, he played the fastidious best friend in several Rock Hudson-Doris Day features, including 1959's Pillow Talk.

He was born Leonard Rosenbergin in Tulsa, Okla., on Feb.26, 1920. He went to Northwestern University in Chicago and Columbia University in New York, as well as studying at the Neighborhood Playhouse School of the Theatre in New York and the Officer Candidate School at Fort Monmouth, N.J.

Randall became a father for the first time at the age of 77 with his second wife, Heather Harlan, who is 50 years his junior. They had a daughter and a son together.

Randall was reportedly sick all winter. He was hospitalized after starring for a month in Right You Are, a revival of Luigi Pirandello's play by the National Actors Theatre, which he founded.

In a tribute to the actor, lights at all Broadway theatres were to be dimmed at 8 p.m. eastern on Tuesday evening.

He joked in September about how he envisioned his funeral: U.S. President George W. Bush and Vice President Dick Cheney would show up to pay their respects, but they'd be turned away, because his family knows he didn't like them.