397791940 has 96 divisors (see below), whose sum is σ = 1036836864. Its totient is φ = 124830720.

The previous prime is 397791929. The next prime is 397791941. The reversal of 397791940 is 49197793.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (397791941) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 230280 + ... + 232000.

It is an arithmetic number, because the mean of its divisors is an integer number (10800384).

Almost surely, 2^397791940 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 397791940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (518418432).

397791940 is an abundant number, since it is smaller than the sum of its proper divisors (639044924).

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

397791940 is a wasteful number, since it uses less digits than its factorization.

397791940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1877 (or 1875 counting only the distinct ones).

The product of its (nonzero) digits is 428652, while the sum is 49.

The square root of 397791940 is about 19944.7221088688. The cubic root of 397791940 is about 735.4480369505.

The spelling of 397791940 in words is "three hundred ninety-seven million, seven hundred ninety-one thousand, nine hundred forty".