398558989 has 2 divisors, whose sum is σ = 398558990. Its totient is φ = 398558988.

The previous prime is 398558929. The next prime is 398559001. The reversal of 398558989 is 989855893.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 343175625 + 55383364 = 18525^2 + 7442^2 .

It is a cyclic number.

It is not a de Polignac number, because 398558989 - 2¹⁷ = 398427917 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 398558989.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (398558929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199279494 + 199279495.

It is an arithmetic number, because the mean of its divisors is an integer number (199279495).

Almost surely, 2^398558989 is an apocalyptic number.

It is an amenable number.

398558989 is a deficient number, since it is larger than the sum of its proper divisors (1).

398558989 is an equidigital number, since it uses as much as digits as its factorization.

398558989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27993600, while the sum is 64.

The square root of 398558989 is about 19963.9422209142. The cubic root of 398558989 is about 735.9204467861.

The spelling of 398558989 in words is "three hundred ninety-eight million, five hundred fifty-eight thousand, nine hundred eighty-nine".