How much do cast members of a sitcom receive everytime episodes of that particular show is repeated?

Anywhere from nothing at all to millions. It depends on lots of factors.

Millions ?? Gee who gets that much. Thousands but Millions. Gosh.

Jerry Seinfeld makes ALOT from syndication, because he is also a producer/creator or whatever, but I dont know if it is on a per episode basis, I think you buy the package and then could show it 24/7 for a year if you wanted to