398991844 has 12 divisors (see below), whose sum is σ = 711410364. Its totient is φ = 195731744.

The previous prime is 398991799. The next prime is 398991847. The reversal of 398991844 is 448199893.

It can be written as a sum of positive squares in 2 ways, for example, as 176624100 + 222367744 = 13290^2 + 14912^2 .

It is not an unprimeable number, because it can be changed into a prime (398991847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 940807 + ... + 941230.

It is an arithmetic number, because the mean of its divisors is an integer number (59284197).

Almost surely, 2^398991844 is an apocalyptic number.

It is an amenable number.

398991844 is a deficient number, since it is larger than the sum of its proper divisors (312418520).

398991844 is a wasteful number, since it uses less digits than its factorization.

398991844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1882094 (or 1882092 counting only the distinct ones).

The product of its digits is 2239488, while the sum is 55.

The square root of 398991844 is about 19974.7801990410. The cubic root of 398991844 is about 736.1867658706.

The spelling of 398991844 in words is "three hundred ninety-eight million, nine hundred ninety-one thousand, eight hundred forty-four".