How old would Hannes Keller be today?

Hannes Keller was a Swiss physicist, mathematician, deep diving pioneer, and entrepreneur. In 1962, he reached a depth of 1,000 feet (300 m) in open ocean. In the 1970s through the 1980s, Keller made himself a name as an entrepreneur in the IT industry. Keller was also an amateur classical pianist who produced two CDs and occasionally performed for audiences of up to 2000 people.