397201809 has 24 divisors (see below), whose sum is σ = 550257280. Its totient is φ = 254816640.

The previous prime is 397201807. The next prime is 397201817. The reversal of 397201809 is 908102793.

It is not a de Polignac number, because 397201809 - 2¹ = 397201807 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (397201801) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 397899 + ... + 398895.

Almost surely, 2^397201809 is an apocalyptic number.

It is an amenable number.

397201809 is a deficient number, since it is larger than the sum of its proper divisors (153055471).

397201809 is an equidigital number, since it uses as much as digits as its factorization.

397201809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1161 (or 1120 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 39.

The square root of 397201809 is about 19929.9224534367. The cubic root of 397201809 is about 735.0841738019.

The spelling of 397201809 in words is "three hundred ninety-seven million, two hundred one thousand, eight hundred nine".