397821996 has 96 divisors (see below), whose sum is σ = 1211750400. Its totient is φ = 111274560.

The previous prime is 397821923. The next prime is 397822043. The reversal of 397821996 is 699128793.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2565 + ... + 28323.

It is an arithmetic number, because the mean of its divisors is an integer number (12622400).

Almost surely, 2^397821996 is an apocalyptic number.

397821996 is a gapful number since it is divisible by the number (36) 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 397821996, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (605875200).

397821996 is an abundant number, since it is smaller than the sum of its proper divisors (813928404).

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

397821996 is a wasteful number, since it uses less digits than its factorization.

397821996 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25796 (or 25788 counting only the distinct ones).

The product of its digits is 1469664, while the sum is 54.

The square root of 397821996 is about 19945.4755771829. The cubic root of 397821996 is about 735.4665592543.

The spelling of 397821996 in words is "three hundred ninety-seven million, eight hundred twenty-one thousand, nine hundred ninety-six".