91031504256 has 1152 divisors, whose sum is σ = 358753224960. Its totient is φ = 21507932160.

The previous prime is 91031504227. The next prime is 91031504269. The reversal of 91031504256 is 65240513019.

91031504256 is a `hidden beast` number, since 91 + 0 + 315 + 0 + 4 + 256 = 666.

It is a tau number, because it is divible by the number of its divisors (1152).

It is a super-2 number, since 2×91031504256² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 91031504256.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 1358679135 + ... + 1358679201.

It is an arithmetic number, because the mean of its divisors is an integer number (311417730).

Almost surely, 2^91031504256 is an apocalyptic number.

91031504256 is a gapful number since it is divisible by the number (96) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91031504256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (179376612480).

91031504256 is an abundant number, since it is smaller than the sum of its proper divisors (267721720704).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91031504256 is a wasteful number, since it uses less digits than its factorization.

91031504256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192 (or 160 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The spelling of 91031504256 in words is "ninety-one billion, thirty-one million, five hundred four thousand, two hundred fifty-six".