91491256502 has 16 divisors (see below), whose sum is σ = 138305795760. Its totient is φ = 45390444288.

The previous prime is 91491256487. The next prime is 91491256573. The reversal of 91491256502 is 20565219419.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 116003 + ... + 443214.

It is an arithmetic number, because the mean of its divisors is an integer number (8644112235).

Almost surely, 2^91491256502 is an apocalyptic number.

91491256502 is a deficient number, since it is larger than the sum of its proper divisors (46814539258).

91491256502 is a wasteful number, since it uses less digits than its factorization.

91491256502 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 559855.

The product of its (nonzero) digits is 194400, while the sum is 44.

The spelling of 91491256502 in words is "ninety-one billion, four hundred ninety-one million, two hundred fifty-six thousand, five hundred two".