397900720 has 80 divisors (see below), whose sum is σ = 1075288320. Its totient is φ = 134099712.

The previous prime is 397900697. The next prime is 397900721. The reversal of 397900720 is 27009793.

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

It is a self number, because there is not a number n which added to its sum of digits gives 397900720.

It is not an unprimeable number, because it can be changed into a prime (397900721) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 27019 + ... + 39061.

It is an arithmetic number, because the mean of its divisors is an integer number (13441104).

Almost surely, 2^397900720 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 397900720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (537644160).

397900720 is an abundant number, since it is smaller than the sum of its proper divisors (677387600).

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

397900720 is a wasteful number, since it uses less digits than its factorization.

397900720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12122 (or 12116 counting only the distinct ones).

The product of its (nonzero) digits is 23814, while the sum is 37.

The square root of 397900720 is about 19947.4489597041. The cubic root of 397900720 is about 735.5150692674.

The spelling of 397900720 in words is "three hundred ninety-seven million, nine hundred thousand, seven hundred twenty".