398884891 has 2 divisors, whose sum is σ = 398884892. Its totient is φ = 398884890.

The previous prime is 398884861. The next prime is 398884903. The reversal of 398884891 is 198488893.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 398884891 - 2²³ = 390496283 is a prime.

It is not a weakly prime, because it can be changed into another prime (398884831) 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 as a sum of consecutive naturals, namely, 199442445 + 199442446.

It is an arithmetic number, because the mean of its divisors is an integer number (199442446).

Almost surely, 2^398884891 is an apocalyptic number.

398884891 is a deficient number, since it is larger than the sum of its proper divisors (1).

398884891 is an equidigital number, since it uses as much as digits as its factorization.

398884891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3981312, while the sum is 58.

The square root of 398884891 is about 19972.1028186819. The cubic root of 398884891 is about 736.1209797142.

The spelling of 398884891 in words is "three hundred ninety-eight million, eight hundred eighty-four thousand, eight hundred ninety-one".