397916856 has 24 divisors (see below), whose sum is σ = 1077691680. Its totient is φ = 132638928.

The previous prime is 397916809. The next prime is 397916863. The reversal of 397916856 is 658619793.

It is a tau number, because it is divible by the number of its divisors (24).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2763240 + ... + 2763383.

It is an arithmetic number, because the mean of its divisors is an integer number (44903820).

Almost surely, 2^397916856 is an apocalyptic number.

397916856 is a gapful number since it is divisible by the number (36) formed by its first and last digit.

It is an amenable number.

397916856 is an abundant number, since it is smaller than the sum of its proper divisors (679774824).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

397916856 is a wasteful number, since it uses less digits than its factorization.

397916856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5526635 (or 5526628 counting only the distinct ones).

The product of its digits is 2449440, while the sum is 54.

The square root of 397916856 is about 19947.8534183506. The cubic root of 397916856 is about 735.5250115387.

The spelling of 397916856 in words is "three hundred ninety-seven million, nine hundred sixteen thousand, eight hundred fifty-six".