The Professor Was Never Shirtless
According to Russell Johnson, when he first auditioned for the role of The Professor, the producers insisted that he would take his shirt off in front of the camera. He declined again and again, and at the end got the part without filming even one shirtless scene.
Natalie Schafer was a real life millionaire with a known extravagant lifestyle even before the show aired its first episode. Schafer was married to Louis Calhern, and the two had a profitable real estate business in Beverley Hills. When she passed she left most of her money to her dog. After he passed, most of her money was donated to hospitals in the Los Angeles area.