398989 has 2 divisors, whose sum is σ = 398990. Its totient is φ = 398988.

The previous prime is 398977. The next prime is 399023. The reversal of 398989 is 989893.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 209764 + 189225 = 458^2 + 435^2 .

It is a cyclic number.

It is not a de Polignac number, because 398989 - 2⁹ = 398477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (398969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199494 + 199495.

It is an arithmetic number, because the mean of its divisors is an integer number (199495).

2³⁹⁸⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

398989 is a deficient number, since it is larger than the sum of its proper divisors (1).

398989 is an equidigital number, since it uses as much as digits as its factorization.

398989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 139968, while the sum is 46.

The square root of 398989 is about 631.6557606798. The cubic root of 398989 is about 73.6185016695.

The spelling of 398989 in words is "three hundred ninety-eight thousand, nine hundred eighty-nine".