Roger Apéry (1916 - 1994) was a French mathematician most remembered for Apéry's theorem, to the effect that ζ(3) is an irrational number where ζ denotes the Riemann zeta function.

He was born in Rouen in 1916, taught at the University of Caen , and died after a long illness in 1994.

In 1977, he stunned the mathematical world with his unexpected proof of the irrationality of the sum of the inverse of the cubes of integers. Until that time, despite a distinguished career, he had enjoyed calling himself "the worst mathematician in France" because no single famous theorem bore his name.