91800012 has 24 divisors (see below), whose sum is σ = 219182656. Its totient is φ = 29888208.

The previous prime is 91799999. The next prime is 91800019. The reversal of 91800012 is 21000819.

It is not an unprimeable number, because it can be changed into a prime (91800019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 88438 + ... + 89469.

Almost surely, 2^91800012 is an apocalyptic number.

It is an amenable number.

91800012 is an abundant number, since it is smaller than the sum of its proper divisors (127382644).

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

91800012 is a wasteful number, since it uses less digits than its factorization.

91800012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177957 (or 177955 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 21.

The square root of 91800012 is about 9581.2322798271. The cubic root of 91800012 is about 451.1083985176.

The spelling of 91800012 in words is "ninety-one million, eight hundred thousand, twelve".