397999980 has 144 divisors (see below), whose sum is σ = 1430956800. Its totient is φ = 90963648.

The previous prime is 397999969. The next prime is 397999991. The reversal of 397999980 is 89999793.

It is an interprime number because it is at equal distance from previous prime (397999969) and next prime (397999991).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 28171 + ... + 39869.

It is an arithmetic number, because the mean of its divisors is an integer number (9937200).

Almost surely, 2^397999980 is an apocalyptic number.

397999980 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 397999980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (715478400).

397999980 is an abundant number, since it is smaller than the sum of its proper divisors (1032956820).

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

397999980 is a wasteful number, since it uses less digits than its factorization.

397999980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11730 (or 11716 counting only the distinct ones).

The product of its (nonzero) digits is 9920232, while the sum is 63.

The square root of 397999980 is about 19949.9368420053. The cubic root of 397999980 is about 735.5762245189.

The spelling of 397999980 in words is "three hundred ninety-seven million, nine hundred ninety-nine thousand, nine hundred eighty".