91057304788 has 12 divisors (see below), whose sum is σ = 159917368212. Its totient is φ = 45366628160.

The previous prime is 91057304771. The next prime is 91057304831. The reversal of 91057304788 is 88740375019.

It can be written as a sum of positive squares in 2 ways, for example, as 53936346564 + 37120958224 = 232242^2 + 192668^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40504795 + ... + 40507042.

It is an arithmetic number, because the mean of its divisors is an integer number (13326447351).

Almost surely, 2^91057304788 is an apocalyptic number.

It is an amenable number.

91057304788 is a deficient number, since it is larger than the sum of its proper divisors (68860063424).

91057304788 is a wasteful number, since it uses less digits than its factorization.

91057304788 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81012122 (or 81012120 counting only the distinct ones).

The product of its (nonzero) digits is 1693440, while the sum is 52.

The spelling of 91057304788 in words is "ninety-one billion, fifty-seven million, three hundred four thousand, seven hundred eighty-eight".