397311809 has 16 divisors (see below), whose sum is σ = 416313408. Its totient is φ = 378810432.

The previous prime is 397311791. The next prime is 397311823. The reversal of 397311809 is 908113793.

It is a cyclic number.

It is not a de Polignac number, because 397311809 - 2⁸ = 397311553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (397311829) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 726074 + ... + 726620.

It is an arithmetic number, because the mean of its divisors is an integer number (26019588).

Almost surely, 2^397311809 is an apocalyptic number.

It is an amenable number.

397311809 is a deficient number, since it is larger than the sum of its proper divisors (19001599).

397311809 is a wasteful number, since it uses less digits than its factorization.

397311809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 944.

The product of its (nonzero) digits is 40824, while the sum is 41.

The square root of 397311809 is about 19932.6819319428. The cubic root of 397311809 is about 735.1520249498.

The spelling of 397311809 in words is "three hundred ninety-seven million, three hundred eleven thousand, eight hundred nine".