Anyway, for another time google search is giving the answers.
Must be about 200 M' or more accounts
relative links
https://nordeus.com/press-releases/t...istered-users/
How did Nordeus manage to get 1 million new Top Eleven users in just a month? | start·it
https://en.wikipedia.org/wiki/Top_El...otball_Manager
https://www.pocketgamer.biz/news/612...llion-players/
Gamasutra - Press Releases- Dedicated to the Community, Top Eleven 2019 Kicks Off The Year *

Of course they are not all active or unique but the game must be able to offer to anyone who 's asking to upload his profile picture .