398791866 has 32 divisors (see below), whose sum is σ = 872607168. Its totient is φ = 120496640.

The previous prime is 398791859. The next prime is 398791867. The reversal of 398791866 is 668197893.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (398791867) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14740 + ... + 31856.

It is an arithmetic number, because the mean of its divisors is an integer number (27268974).

Almost surely, 2^398791866 is an apocalyptic number.

398791866 is an abundant number, since it is smaller than the sum of its proper divisors (473815302).

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

398791866 is a wasteful number, since it uses less digits than its factorization.

398791866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17486.

The product of its digits is 3919104, while the sum is 57.

The square root of 398791866 is about 19969.7738094351. The cubic root of 398791866 is about 736.0637510252.

The spelling of 398791866 in words is "three hundred ninety-eight million, seven hundred ninety-one thousand, eight hundred sixty-six".