Dwayne Johnson and Kevin Hart formed a friendship since this film came out and have been best friends ever since.
Dwayne Johnson wears a fanny pack throughout the movie and the film makes multiple comedic references to it. This is a reference to a popular meme, which shows Johnson wearing a fanny pack in the '90s.
Dwayne Johnson gives three nods to Bruce Lee: yellow and black sneakers, a famous Lee pose, and a one inch punch.
When Kevin Hart and Dwayne Johnson's characters first meet, Hart makes a reference to Johnson looking like Hercules. Johnson played the titular character in Hercules: Il guerriero (2014).
From the time when Bob Stone ordered the Uber to it getting to Calvin Joyner's job took exactly six minutes.