397942784 has 56 divisors (see below), whose sum is σ = 822033408. Its totient is φ = 192430080.

The previous prime is 397942781. The next prime is 397942789. The reversal of 397942784 is 487249793.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397942781) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 253169 + ... + 254735.

It is an arithmetic number, because the mean of its divisors is an integer number (14679168).

Almost surely, 2^397942784 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 397942784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (411016704).

397942784 is an abundant number, since it is smaller than the sum of its proper divisors (424090624).

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

397942784 is an equidigital number, since it uses as much as digits as its factorization.

397942784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1624 (or 1600 counting only the distinct ones).

The product of its digits is 3048192, while the sum is 53.

The square root of 397942784 is about 19948.5033022530. The cubic root of 397942784 is about 735.5409866333.

The spelling of 397942784 in words is "three hundred ninety-seven million, nine hundred forty-two thousand, seven hundred eighty-four".