397438189 has 4 divisors (see below), whose sum is σ = 420816924. Its totient is φ = 374059456.

The previous prime is 397438159. The next prime is 397438193. The reversal of 397438189 is 981834793.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 981834793 = 647 ⋅1517519.

It can be written as a sum of positive squares in 2 ways, for example, as 301300164 + 96138025 = 17358^2 + 9805^2 .

It is a cyclic number.

It is not a de Polignac number, because 397438189 - 2²³ = 389049581 is a prime.

It is a super-2 number, since 2×397438189² = 315914228151199442, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397438109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11689342 + ... + 11689375.

It is an arithmetic number, because the mean of its divisors is an integer number (105204231).

Almost surely, 2^397438189 is an apocalyptic number.

It is an amenable number.

397438189 is a deficient number, since it is larger than the sum of its proper divisors (23378735).

397438189 is a wasteful number, since it uses less digits than its factorization.

397438189 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23378734.

The product of its digits is 1306368, while the sum is 52.

The square root of 397438189 is about 19935.8518503725. The cubic root of 397438189 is about 735.2299642924.

The spelling of 397438189 in words is "three hundred ninety-seven million, four hundred thirty-eight thousand, one hundred eighty-nine".