Interesting stats from this site: https://gamstat.com/games/GTA_5/
Total Players
PS4 = 92.4m
PS3 = 58.5m
XBO+360 = 71.8m
9m people have played GTA V on Xbox Platforms in the last month.
4.7m people have earned a trophy in GTA V on PlayStation platforms in the past month.
1.2m people played GTA V on PS4 for the first time in the past month.
380k people played GTA V on Xbox Platforms for the first time in the past month.
Obviously Players will be higher than actual sales due to preowned games, sharing games, multiple accounts etc. But still interesting stats to see.