Just won millions in the lottery? Congratulations! Here's what to do — and more importantly, not to do — to avoid making some very big mistakes.

The latest Mega Millions lottery drawing is Friday evening, Dec. 27, and the total has reached a staggering $1.2 billion.

The question lurking is, what happens when $1 billion becomes routine and people don’t care about it anymore?” said Jonathan D. Cohen, author of the 2022 book “For a Dollar and a Dream: State Lotteries in Modern America.

Friday’s Mega Millions drawing is worth an estimated $1.15 billion, evoking headlines and likely luring more people to convenience stores with dreams of private spacewalks above the earth.