397931904 has 96 divisors (see below), whose sum is σ = 1150968000. Its totient is φ = 131963904.

The previous prime is 397931899. The next prime is 397931917. The reversal of 397931904 is 409139793.

It is a tau number, because it is divible by the number of its divisors (96).

It is a self number, because there is not a number n which added to its sum of digits gives 397931904.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 256122 + ... + 257670.

It is an arithmetic number, because the mean of its divisors is an integer number (11989250).

Almost surely, 2^397931904 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 397931904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (575484000).

397931904 is an abundant number, since it is smaller than the sum of its proper divisors (753036096).

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

397931904 is a wasteful number, since it uses less digits than its factorization.

397931904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1792 (or 1777 counting only the distinct ones).

The product of its (nonzero) digits is 183708, while the sum is 45.

The square root of 397931904 is about 19948.2305982260. The cubic root of 397931904 is about 735.5342831915.

The spelling of 397931904 in words is "three hundred ninety-seven million, nine hundred thirty-one thousand, nine hundred four".