31604 has 6 divisors (see below), whose sum is σ = 55314. Its totient is φ = 15800.

The previous prime is 31601. The next prime is 31607. The reversal of 31604 is 40613.

It is an interprime number because it is at equal distance from previous prime (31601) and next prime (31607).

It can be written as a sum of positive squares in only one way, i.e., 28900 + 2704 = 170^2 + 52^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3947 + ... + 3954.

It is an arithmetic number, because the mean of its divisors is an integer number (9219).

2³¹⁶⁰⁴ is an apocalyptic number.

It is an amenable number.

31604 is a deficient number, since it is larger than the sum of its proper divisors (23710).

31604 is a wasteful number, since it uses less digits than its factorization.

31604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7905 (or 7903 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 31604 is about 177.7751388693. The cubic root of 31604 is about 31.6165164953.

Subtracting 31604 from its reverse (40613), we obtain a palindrome (9009).

The spelling of 31604 in words is "thirty-one thousand, six hundred four".