31689937 has 4 divisors (see below), whose sum is σ = 31719280. Its totient is φ = 31660596.

The previous prime is 31689923. The next prime is 31689941. The reversal of 31689937 is 73998613.

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.

It is a cyclic number.

It is not a de Polignac number, because 31689937 - 2⁷ = 31689809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31689137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12987 + ... + 15232.

It is an arithmetic number, because the mean of its divisors is an integer number (7929820).

Almost surely, 2^31689937 is an apocalyptic number.

It is an amenable number.

31689937 is a deficient number, since it is larger than the sum of its proper divisors (29343).

31689937 is a wasteful number, since it uses less digits than its factorization.

31689937 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29342.

The product of its digits is 244944, while the sum is 46.

The square root of 31689937 is about 5629.3815823765. The cubic root of 31689937 is about 316.4514757145.

The spelling of 31689937 in words is "thirty-one million, six hundred eighty-nine thousand, nine hundred thirty-seven".