Conversation so far:
who's won the most titles in English football
Manchester United are currently the record title winners in the English top flight having won the division a total of 20 times since 1889.
what year was the most recent title Manchester United won  in the English top flight
Manchester United's most recent title came in the 2012-13 season, which was Alex Ferguson's final season of management before his retirement.
what league does Manchester United play in
Manchester United competes in the Premier League, the top flight of English football.

Question: how many competing teams
Self-contained rewrite: how many competing teams are there in the Premier League