397688357 has 4 divisors (see below), whose sum is σ = 433841856. Its totient is φ = 361534860.

The previous prime is 397688351. The next prime is 397688383. The reversal of 397688357 is 753886793.

It is a happy number.

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 a cyclic number.

It is not a de Polignac number, because 397688357 - 2²⁸ = 129252901 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397688351) 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, 18076733 + ... + 18076754.

It is an arithmetic number, because the mean of its divisors is an integer number (108460464).

Almost surely, 2^397688357 is an apocalyptic number.

It is an amenable number.

397688357 is a deficient number, since it is larger than the sum of its proper divisors (36153499).

397688357 is a wasteful number, since it uses less digits than its factorization.

397688357 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36153498.

The product of its digits is 7620480, while the sum is 56.

The square root of 397688357 is about 19942.1251876524. The cubic root of 397688357 is about 735.3841957649.

The spelling of 397688357 in words is "three hundred ninety-seven million, six hundred eighty-eight thousand, three hundred fifty-seven".