397939920 has 80 divisors (see below), whose sum is σ = 1409850240. Its totient is φ = 90957312.

The previous prime is 397939907. The next prime is 397939939. The reversal of 397939920 is 29939793.

It is a tau number, because it is divible by the number of its divisors (80).

It is a hoax number, since the sum of its digits (51) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 116755 + ... + 120114.

It is an arithmetic number, because the mean of its divisors is an integer number (17623128).

Almost surely, 2^397939920 is an apocalyptic number.

397939920 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

397939920 is an abundant number, since it is smaller than the sum of its proper divisors (1011910320).

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

397939920 is a wasteful number, since it uses less digits than its factorization.

397939920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 236892 (or 236886 counting only the distinct ones).

The product of its (nonzero) digits is 826686, while the sum is 51.

The square root of 397939920 is about 19948.4315172898. The cubic root of 397939920 is about 735.5392220627.

The spelling of 397939920 in words is "three hundred ninety-seven million, nine hundred thirty-nine thousand, nine hundred twenty".