The UEFA Champions League final in 2016 attracted 350 million global viewers.[1] I am supposing the 2017 event wasn't too much less than this.
The 2017 Indian Premier League (IPL) final had 324 million viewers according to one source.
[1] http://www.pennlive.com/sports/index.ssf/2017/02/super_bowl_...
[2] http://www.espncricinfo.com/story/_/id/19660717/billion-peop...