91031013 has 8 divisors (see below), whose sum is σ = 134860800. Its totient is φ = 60687324.

The previous prime is 91031011. The next prime is 91031021. The reversal of 91031013 is 31013019.

It is not a de Polignac number, because 91031013 - 2¹ = 91031011 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91031011) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1685733 + ... + 1685786.

It is an arithmetic number, because the mean of its divisors is an integer number (16857600).

Almost surely, 2^91031013 is an apocalyptic number.

It is an amenable number.

91031013 is a deficient number, since it is larger than the sum of its proper divisors (43829787).

91031013 is a wasteful number, since it uses less digits than its factorization.

91031013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3371528 (or 3371522 counting only the distinct ones).

The product of its (nonzero) digits is 81, while the sum is 18.

The square root of 91031013 is about 9541.0173985797. The cubic root of 91031013 is about 449.8452356683.

The spelling of 91031013 in words is "ninety-one million, thirty-one thousand, thirteen".