ELTON JOHN, MARIAH CAREY: Russian to the Bank

Elton John and Mariah Carey both earned seven-figure paychecks over the weekend -- as wedding singers for a Russian billionaire's granddaughter.

The chart-toppers jetted over to London for the wedding of 19-year-old Irene Kogan, whose grandpa Valery is one of Russia's richest men. Elton was actually in the weird position of serving as Mariah's opening act -- but TMZ says he delivered a 12-song set for his $4 million payday. Mimi took in the same amount for her performance.