91158631 has 4 divisors (see below), whose sum is σ = 94099264. Its totient is φ = 88218000.

The previous prime is 91158619. The next prime is 91158643. The reversal of 91158631 is 13685119.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (91158619) and next prime (91158643).

It is a cyclic number.

It is not a de Polignac number, because 91158631 - 2⁷ = 91158503 is a prime.

It is a super-2 number, since 2×91158631² = 16619792011588322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91158611) 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 3 ways as a sum of consecutive naturals, for example, 1470270 + ... + 1470331.

It is an arithmetic number, because the mean of its divisors is an integer number (23524816).

Almost surely, 2^91158631 is an apocalyptic number.

91158631 is a deficient number, since it is larger than the sum of its proper divisors (2940633).

91158631 is a wasteful number, since it uses less digits than its factorization.

91158631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2940632.

The product of its digits is 6480, while the sum is 34.

The square root of 91158631 is about 9547.7029174561. The cubic root of 91158631 is about 450.0553528617.

The spelling of 91158631 in words is "ninety-one million, one hundred fifty-eight thousand, six hundred thirty-one".