In a press conference at 23:30 JST (14:30 UST), the exchange's president Wakata Koichi Yoshihiro and chief operating officer Yusuke Otsuka estimated its loss at 58 billion yen (approx. $533 million). According to Bloomberg, which attended the conference, 500 million NEM tokens were taken from Coincheck's digital wallets.
https://www.coindesk.com/coincheck-confirms-crypto-hack-loss-larger-than-mt-gox/