91321840512 has 96 divisors (see below), whose sum is σ = 300329293680. Its totient is φ = 26091952128.

The previous prime is 91321840471. The next prime is 91321840517. The reversal of 91321840512 is 21504812319.

91321840512 is a `hidden beast` number, since 9 + 132 + 1 + 8 + 4 + 0 + 512 = 666.

It is a tau number, because it is divible by the number of its divisors (96).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91321840517) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5654253 + ... + 5670380.

Almost surely, 2^91321840512 is an apocalyptic number.

It is an amenable number.

91321840512 is an abundant number, since it is smaller than the sum of its proper divisors (209007453168).

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

91321840512 is a wasteful number, since it uses less digits than its factorization.

91321840512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11324660 (or 11324645 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The spelling of 91321840512 in words is "ninety-one billion, three hundred twenty-one million, eight hundred forty thousand, five hundred twelve".