When people say recite Pi is there some calculation involved or are they just memorising a large string of numbers?
Sounds like a remarkable guy. But, and not to nitpick, but calling him "the greatest mathematician of his era" is a bit ridiculous. This was the era of Hilbert, von Neumann, Gödel, Turing, Einstein, Ramanujan...
Yeah, the mainstream will probably never get the distinction between mathematics and arithmetics straight.