91031601 has 4 divisors (see below), whose sum is σ = 121375472. Its totient is φ = 60687732.

The previous prime is 91031579. The next prime is 91031623. The reversal of 91031601 is 10613019.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 10613019 = 3 ⋅3537673.

It is an interprime number because it is at equal distance from previous prime (91031579) and next prime (91031623).

It is not a de Polignac number, because 91031601 - 2⁹ = 91031089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91031671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15171931 + ... + 15171936.

It is an arithmetic number, because the mean of its divisors is an integer number (30343868).

Almost surely, 2^91031601 is an apocalyptic number.

It is an amenable number.

91031601 is a deficient number, since it is larger than the sum of its proper divisors (30343871).

91031601 is a wasteful number, since it uses less digits than its factorization.

91031601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30343870.

The product of its (nonzero) digits is 162, while the sum is 21.

The square root of 91031601 is about 9541.0482128538. The cubic root of 91031601 is about 449.8462042336.

The spelling of 91031601 in words is "ninety-one million, thirty-one thousand, six hundred one".