91191012 has 24 divisors (see below), whose sum is σ = 232122912. Its totient is φ = 27633600.

The previous prime is 91191007. The next prime is 91191019. The reversal of 91191012 is 21019119.

It is not an unprimeable number, because it can be changed into a prime (91191019) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 345289 + ... + 345552.

It is an arithmetic number, because the mean of its divisors is an integer number (9671788).

Almost surely, 2^91191012 is an apocalyptic number.

It is an amenable number.

91191012 is an abundant number, since it is smaller than the sum of its proper divisors (140931900).

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

91191012 is a wasteful number, since it uses less digits than its factorization.

91191012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 690859 (or 690857 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 24.

The square root of 91191012 is about 9549.3985150898. The cubic root of 91191012 is about 450.1086355003.

The spelling of 91191012 in words is "ninety-one million, one hundred ninety-one thousand, twelve".