31686425 has 12 divisors (see below), whose sum is σ = 39418236. Its totient is φ = 25267200.

The previous prime is 31686367. The next prime is 31686437. The reversal of 31686425 is 52468613.

It can be written as a sum of positive squares in 6 ways, for example, as 2569609 + 29116816 = 1603^2 + 5396^2 .

It is not a de Polignac number, because 31686425 - 2⁸ = 31686169 is a prime.

It is a hoax number, since the sum of its digits (35) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6545 + ... + 10305.

It is an arithmetic number, because the mean of its divisors is an integer number (3284853).

Almost surely, 2^31686425 is an apocalyptic number.

It is an amenable number.

31686425 is a deficient number, since it is larger than the sum of its proper divisors (7731811).

31686425 is a wasteful number, since it uses less digits than its factorization.

31686425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4108 (or 4103 counting only the distinct ones).

The product of its digits is 34560, while the sum is 35.

The square root of 31686425 is about 5629.0696389368. The cubic root of 31686425 is about 316.4397851617.

The spelling of 31686425 in words is "thirty-one million, six hundred eighty-six thousand, four hundred twenty-five".