Zerah Colburn
Zerah Colburn (1804-1839) was a child prodigy possessing phenomenal skills at mathematics, particularly in doing complex calculations swiftly in his mind. For example, when asked whether the number 4294967297 is a prime number, Colburn replied after doing a brief mental calculation that it was not, because it had the divisor 641.[1]
Attracting attention, Colburn was sent to school at the Westminster School in London, where he met and inspired a young William Hamilton to become the greatest mathematician and scientist in the history of Ireland.[2]
Colburn seemed to lose his remarkable skills as he grew older, and he did not contribute anything theoretical or lasting to the field of mathematics. He attributed his skills to a tremendous memory.