Imagine you could do complex calculations in your head without even trying, recite pi up to 22,000 digits with no memorization. Daniel Tammet can do all of these things because the numbers and the answers to equations just pop into his head as he ‘sees’ different shapes/colors/textures that represent numbers to him. Numbers up to 10,000 have their own distinct shape. As he imagines pi, there is a beautiful numerical-landscape composed of these shapes that unfold in his mind and reveal the next set of digits to him. Getting different senses mixed up like that is called Synesthesia. I guarantee he knows more languages than you also. I definitely recommend watching the entire documentary, it’s really amazing to watch and you’ll learn about even more people with abilities like this. He also did a TED Talk, Different Ways of Knowing, check that out as well.