397856638 has 8 divisors (see below), whose sum is σ = 596882088. Its totient is φ = 198895944.

The previous prime is 397856633. The next prime is 397856639. The reversal of 397856638 is 836658793.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397856633) 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, 4420 + ... + 28552.

It is an arithmetic number, because the mean of its divisors is an integer number (74610261).

Almost surely, 2^397856638 is an apocalyptic number.

397856638 is a deficient number, since it is larger than the sum of its proper divisors (199025450).

397856638 is a wasteful number, since it uses less digits than its factorization.

397856638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32378.

The product of its digits is 6531840, while the sum is 55.

The square root of 397856638 is about 19946.3439757766. The cubic root of 397856638 is about 735.4879065682.

The spelling of 397856638 in words is "three hundred ninety-seven million, eight hundred fifty-six thousand, six hundred thirty-eight".