91991100902 has 16 divisors (see below), whose sum is σ = 143025868800. Its totient is φ = 44345024328.

The previous prime is 91991100889. The next prime is 91991100913. The reversal of 91991100902 is 20900119919.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 91991100902.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7296902 + ... + 7309497.

It is an arithmetic number, because the mean of its divisors is an integer number (8939116800).

Almost surely, 2^91991100902 is an apocalyptic number.

91991100902 is a deficient number, since it is larger than the sum of its proper divisors (51034767898).

91991100902 is a wasteful number, since it uses less digits than its factorization.

91991100902 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14606515.

The product of its (nonzero) digits is 13122, while the sum is 41.

The spelling of 91991100902 in words is "ninety-one billion, nine hundred ninety-one million, one hundred thousand, nine hundred two".