Yea, Regis really flustered him on that question and made him second guess himself even though he had the right answer.

What's extra funny about that is that one of his The View appearances (linked above) was the day of or soon before his Millionaire appearance. One of the hosts said something along the lines of "you think he's dumb here, just wait until his appearance on Millionaire", and of course they all cackle at that. Then he goes and gives a great performance.

He said that one of his fav quotes was from Letterman, something along the lines of "People hate you if they think you're smarter than them". He always played the idiot which made him more likeable, but he was always the sharpest cat in the room. RIP to a true legend.