Well, Richard Petty was one of the older legends of NASCAR (he raced back in the '60s, '70s, and '80s), so I don't think he really got as rich as today's drivers do, despite the immense success he had back in those days.
45
This number was used by his grandson, Adam Petty, who tragically died in a crash just as his racing career got started back in 2000, so we'll never know if he could have been anywhere as good of a stock car racer as his legendary grandfather was.