Elton John -- I'm Still Standing ... And Making Over $500K A Show

Now we know how he can afford that Million Dollar Piano … TMZ has learned Elton John has bumped Britney Spears in her Vegas run by hauling in more than $500K a show.

Elton’s definitely in the driver's seat. According to his deal he gets 88% of the door for every show. He also has a sign off on ticket prices, which range from $55 to $1,000 for VIP seats.

Captain Fantastic is putting Britney's $475K take a show to shame, because he's doing it with fewer seats -- The Colosseum only seats 4,296 while Britney's show at Planet Hollywood has 4,600.

The show began Friday and runs through April 14.

We reached out to Elton, but he's too rich to comment.