While this is impressive, I gotta bring up some potential asterisk here since it was quite a big deal here.
In case you haven't heard it yet.
There was a production mishaps for Asia release, resulting in Asia copies label "English Version" only contain Chinese language! Atlus only put up the notice right before the release, and so customer can request to get a replacement digital code initially, later promised to add physical copy as an option.
And here's the big thing: Would this affect their sale counts for this announcement? It's hard to say but it would be wild think about that the game manage to reach a million copy only because some people had to issue a replacement.