31640404 has 12 divisors (see below), whose sum is σ = 55547604. Its totient is φ = 15769664.

The previous prime is 31640351. The next prime is 31640407. The reversal of 31640404 is 40404613.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 10956100 + 20684304 = 3310^2 + 4548^2 .

It is a super-2 number, since 2×31640404² = 2002230330566432, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31640407) 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, 11209 + ... + 13744.

It is an arithmetic number, because the mean of its divisors is an integer number (4628967).

Almost surely, 2^31640404 is an apocalyptic number.

It is an amenable number.

31640404 is a deficient number, since it is larger than the sum of its proper divisors (23907200).

31640404 is a wasteful number, since it uses less digits than its factorization.

31640404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25274 (or 25272 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 22.

The square root of 31640404 is about 5624.9803555213. The cubic root of 31640404 is about 316.2865130968.

The spelling of 31640404 in words is "thirty-one million, six hundred forty thousand, four hundred four".