31087 has 4 divisors (see below), whose sum is σ = 35536. Its totient is φ = 26640.

The previous prime is 31081. The next prime is 31091. The reversal of 31087 is 78013.

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 31087 - 2³ = 31079 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31081) 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, 2214 + ... + 2227.

It is an arithmetic number, because the mean of its divisors is an integer number (8884).

2³¹⁰⁸⁷ is an apocalyptic number.

31087 is a deficient number, since it is larger than the sum of its proper divisors (4449).

31087 is an equidigital number, since it uses as much as digits as its factorization.

31087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4448.

The product of its (nonzero) digits is 168, while the sum is 19.

The square root of 31087 is about 176.3150589144. The cubic root of 31087 is about 31.4431661849.

The spelling of 31087 in words is "thirty-one thousand, eighty-seven".