It seems that winners don't actually get the million-dollar prize due to taxes and rules, and that also applies to Season 19 winner Richard Goodall. There's a disclaimer that flashes by at the foot of every single episode of the contest that reads in part,

Richard Goodall is the winner of 'AGT' season 19. But there is a complicated reason why the former janitor won't receive the total $1 million prize.

Goodall won America’s hearts throughout his time on AGT with soulful renditions of “How Am I Supposed to Live Without You,” “Eye of the Tiger,” and “Faithfully.” He was crowned the Season 19 champion on Tuesday night, beating out dog act Rani & Rhythm, who finished as runner-up.