A son, Mark Callas, tells The Associated Press that Callas died Thursday in a hospice.
Clark County Coroner Mike Murphy says the death was from natural causes.
Callas toured with Frank Sinatra and Tom Jones, and had a screen part with Jerry Lewis in "The Big Mouth" in 1967.
His facial expressions and rapid-fire comedy also made Callas a favorite on the "Tonight Show" with Johnny Carson.
He also worked with Mel Brooks and was the voice of Elliot in Disney's "Pete's Dragon."
