397478189 has 4 divisors (see below), whose sum is σ = 397689180. Its totient is φ = 397267200.

The previous prime is 397478171. The next prime is 397478219. The reversal of 397478189 is 981874793.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 90878089 + 306600100 = 9533^2 + 17510^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-397478189 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 (397478129) 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, 102644 + ... + 106445.

It is an arithmetic number, because the mean of its divisors is an integer number (99422295).

Almost surely, 2^397478189 is an apocalyptic number.

It is an amenable number.

397478189 is a deficient number, since it is larger than the sum of its proper divisors (210991).

397478189 is a wasteful number, since it uses less digits than its factorization.

397478189 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210990.

The product of its digits is 3048192, while the sum is 56.

The square root of 397478189 is about 19936.8550428597. The cubic root of 397478189 is about 735.2546291022.

The spelling of 397478189 in words is "three hundred ninety-seven million, four hundred seventy-eight thousand, one hundred eighty-nine".