31890087 has 12 divisors (see below), whose sum is σ = 47187504. Its totient is φ = 20741280.

The previous prime is 31890073. The next prime is 31890091. The reversal of 31890087 is 78009813.

It is not a de Polignac number, because 31890087 - 2⁴ = 31890071 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31890587) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 42843 + ... + 43580.

It is an arithmetic number, because the mean of its divisors is an integer number (3932292).

Almost surely, 2^31890087 is an apocalyptic number.

31890087 is a deficient number, since it is larger than the sum of its proper divisors (15297417).

31890087 is a wasteful number, since it uses less digits than its factorization.

31890087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86470 (or 86467 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 36.

The square root of 31890087 is about 5647.1308644302. The cubic root of 31890087 is about 317.1163017349.

The spelling of 31890087 in words is "thirty-one million, eight hundred ninety thousand, eighty-seven".