397989 has 6 divisors (see below), whose sum is σ = 574886. Its totient is φ = 265320.

The previous prime is 397981. The next prime is 398011. The reversal of 397989 is 989793.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 396900 + 1089 = 630^2 + 33^2 .

It is not a de Polignac number, because 397989 - 2³ = 397981 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397981) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 22102 + ... + 22119.

2³⁹⁷⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

397989 is a deficient number, since it is larger than the sum of its proper divisors (176897).

397989 is a wasteful number, since it uses less digits than its factorization.

397989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44227 (or 44224 counting only the distinct ones).

The product of its digits is 122472, while the sum is 45.

The square root of 397989 is about 630.8636936772. The cubic root of 397989 is about 73.5569460112.

The spelling of 397989 in words is "three hundred ninety-seven thousand, nine hundred eighty-nine".