398091664 has 20 divisors (see below), whose sum is σ = 771828700. Its totient is φ = 198910080.

The previous prime is 398091647. The next prime is 398091731. The reversal of 398091664 is 466190893.

It can be written as a sum of positive squares in 2 ways, for example, as 221414400 + 176677264 = 14880^2 + 13292^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18262 + ... + 33610.

It is an arithmetic number, because the mean of its divisors is an integer number (38591435).

Almost surely, 2^398091664 is an apocalyptic number.

It is an amenable number.

398091664 is a deficient number, since it is larger than the sum of its proper divisors (373737036).

398091664 is a wasteful number, since it uses less digits than its factorization.

398091664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16978 (or 16972 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 46.

The square root of 398091664 is about 19952.2345615723. The cubic root of 398091664 is about 735.6327030750.

The spelling of 398091664 in words is "three hundred ninety-eight million, ninety-one thousand, six hundred sixty-four".