397904 has 20 divisors (see below), whose sum is σ = 830676. Its totient is φ = 183552.

The previous prime is 397897. The next prime is 397907. The reversal of 397904 is 409793.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 204304 + 193600 = 452^2 + 440^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397907) by changing a digit.

397904 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 749 + ... + 1164.

2³⁹⁷⁹⁰⁴ is an apocalyptic number.

It is an amenable number.

397904 is an abundant number, since it is smaller than the sum of its proper divisors (432772).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

397904 is a wasteful number, since it uses less digits than its factorization.

397904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1934 (or 1928 counting only the distinct ones).

The product of its (nonzero) digits is 6804, while the sum is 32.

The square root of 397904 is about 630.7963221199. The cubic root of 397904 is about 73.5517090276.

The spelling of 397904 in words is "three hundred ninety-seven thousand, nine hundred four".