Square Enix just announced the news via the NieR Japan Twitter account.
NieR: Automata has had its shipments and digital sales cross 1.5 million units worldwide. This comes after they announced that it had crossed a million in early April. From SteamSpy we have approximate Steam numbers which are little over 360k with an 18k error margin. It isn’t surprising seeing the game do multiples better on PlayStation 4 but that number is still respectable.
— NieR公式PRアカウント (@NieR_JPN) May 30, 2017
NieR: Automata is available on PlayStation 4 and Steam. Read our review here.