Conversation so far:
What is AKB48?
AKB48 (pronounced A.K.B. Forty-Eight) are a Japanese idol girl group named after the Akihabara area in Tokyo.
How many teams are in AKB48?
As of October 30, 2019 the group consists of 108 members.
Did others in the group embark on solo careers like Atsuko Maeda?
Starting in 2014, the members compete in a knockout tournament where the winner would debut as a soloist or, if she was already a soloist, would perform a solo concert.

Question: Was AKB48 very successful?
Self-contained rewrite: Was AKB48 very successful?