The victim, from London, was a passenger in a Toyota Corolla in collision with a VW Touareg between junction four for Snodland and junction three for the M26.
The driver of the Corolla, a 37-year-old man from Orpington, London, was arrested.
The accident was just after 03:30 GMT.
Anyone with information is urged to contact Kent Police.
A man died in a two-car crash on the M20 in which one of the vehicles was believed to be travelling the wrong way.