397639645 has 16 divisors (see below), whose sum is σ = 522587520. Its totient is φ = 288661824.

The previous prime is 397639631. The next prime is 397639651. The reversal of 397639645 is 546936793.

It is a cyclic number.

It is not a de Polignac number, because 397639645 - 2⁹ = 397639133 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 397639592 and 397639601.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48009 + ... + 55678.

It is an arithmetic number, because the mean of its divisors is an integer number (32661720).

Almost surely, 2^397639645 is an apocalyptic number.

It is an amenable number.

397639645 is a deficient number, since it is larger than the sum of its proper divisors (124947875).

397639645 is a wasteful number, since it uses less digits than its factorization.

397639645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103764.

The product of its digits is 3674160, while the sum is 52.

The square root of 397639645 is about 19940.9038160260. The cubic root of 397639645 is about 735.3541693241.

The spelling of 397639645 in words is "three hundred ninety-seven million, six hundred thirty-nine thousand, six hundred forty-five".