At one point Superman was officially recognized as the 3 most famous fictional characters along with Tarzan and Mickey Mouse. That was BEFORE the 1st Superman movie.
I remember that Harlan Ellison liked to mention this factoid but I never saw the actual source of this info.
I did, this was way back, I remember when it was 1st mention, it made the news, during a second survey, in the 80's. Mickey and Superman made the top ten, the rest were real people.