 Niven's constant

In number theory, Niven's constant, named after Ivan Niven, is the largest exponent appearing in the prime factorization of any natural number "n" "on average".More precisely, if we define "H"(1) = 1 and "H"("n") = the largest exponent appearing in the unique prime factorization of a natural number "n" > 1, then Niven's constant is given by

where ζ("k") is the value of the Riemann zeta function at the point "k" (Niven, 1969).