31092991 has 4 divisors (see below), whose sum is σ = 31754592. Its totient is φ = 30431392.

The previous prime is 31092979. The next prime is 31093001. The reversal of 31092991 is 19929013.

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

It is a cyclic number.

It is not a de Polignac number, because 31092991 - 2¹⁵ = 31060223 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31092491) 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, 330730 + ... + 330823.

It is an arithmetic number, because the mean of its divisors is an integer number (7938648).

Almost surely, 2^31092991 is an apocalyptic number.

31092991 is a deficient number, since it is larger than the sum of its proper divisors (661601).

31092991 is an equidigital number, since it uses as much as digits as its factorization.

31092991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 661600.

The product of its (nonzero) digits is 4374, while the sum is 34.

The square root of 31092991 is about 5576.1089480031. The cubic root of 31092991 is about 314.4518593490.

The spelling of 31092991 in words is "thirty-one million, ninety-two thousand, nine hundred ninety-one".