398660789 has 2 divisors, whose sum is σ = 398660790. Its totient is φ = 398660788.

The previous prime is 398660749. The next prime is 398660797. The reversal of 398660789 is 987066893.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 248598289 + 150062500 = 15767^2 + 12250^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-398660789 is a prime.

It is a super-2 number, since 2×398660789² = 317860849372205042, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (398660749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199330394 + 199330395.

It is an arithmetic number, because the mean of its divisors is an integer number (199330395).

Almost surely, 2^398660789 is an apocalyptic number.

It is an amenable number.

398660789 is a deficient number, since it is larger than the sum of its proper divisors (1).

398660789 is an equidigital number, since it uses as much as digits as its factorization.

398660789 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3919104, while the sum is 56.

The square root of 398660789 is about 19966.4916547700. The cubic root of 398660789 is about 735.9830977579.

The spelling of 398660789 in words is "three hundred ninety-eight million, six hundred sixty thousand, seven hundred eighty-nine".