397857 has 4 divisors (see below), whose sum is σ = 530480. Its totient is φ = 265236.

The previous prime is 397849. The next prime is 397867. The reversal of 397857 is 758793.

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 not a de Polignac number, because 397857 - 2³ = 397849 is a prime.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (397807) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66307 + ... + 66312.

It is an arithmetic number, because the mean of its divisors is an integer number (132620).

2³⁹⁷⁸⁵⁷ is an apocalyptic number.

It is an amenable number.

397857 is a deficient number, since it is larger than the sum of its proper divisors (132623).

397857 is a wasteful number, since it uses less digits than its factorization.

397857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132622.

The product of its digits is 52920, while the sum is 39.

The square root of 397857 is about 630.7590665222. The cubic root of 397857 is about 73.5488129636.

The spelling of 397857 in words is "three hundred ninety-seven thousand, eight hundred fifty-seven".