Lil Nas X, Jeff Bezos and Katy Perry Party at Amazon's Employees Bash

Lil Nas X just topped his Billy Ray Cyrus collab by pairing with Jeff Bezos for a huge Amazon office party ... in a freakin' football stadium!! So, yeah ... you could say it was a Prime pairing.

Proving how awesome it is to be the richest man in the world ... Bezos hired Lil Nas AND Katy Perry to perform Tuesday night at Amazon's post-Prime Day concert. No biggie, just a a small get together for more than 45,000 employees at Seattle's CenturyLink Stadium -- and you can tell the boss man was turning up.

Bezos ended up rocking X's graffiti-tagged leather coat, and he posed with Katy and her little dog, Nugget. Lil Nas posted a pic with the caption, "I am now the new owner of amazon and i stole katy perry's dog."

Katy also treated the crowd with her first-ever live performance of "Never Really Over."

Throwing extravagant parties is now Bezos' MO -- just last month he had Taylor Swift headline an Amazon Prime Day concert in NYC. Some critics have bashed him for the lavish events ... saying he should pay employees better instead of staging concerts for them.