91031 has 8 divisors (see below), whose sum is σ = 97680. Its totient is φ = 84672.

The previous prime is 91019. The next prime is 91033. The reversal of 91031 is 13019.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 91031 - 2¹⁰ = 90007 is a prime.

It is a super-2 number, since 2×91031² = 16573285922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 90997 and 91015.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 91031.

It is not an unprimeable number, because it can be changed into a prime (91033) 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, 1211 + ... + 1283.

It is an arithmetic number, because the mean of its divisors is an integer number (12210).

2⁹¹⁰³¹ is an apocalyptic number.

91031 is a deficient number, since it is larger than the sum of its proper divisors (6649).

91031 is a wasteful number, since it uses less digits than its factorization.

91031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145.

The product of its (nonzero) digits is 27, while the sum is 14.

The square root of 91031 is about 301.7134402044. The cubic root of 91031 is about 44.9845214254.

The spelling of 91031 in words is "ninety-one thousand, thirty-one".