6399889 has 2 divisors, whose sum is σ = 6399890. Its totient is φ = 6399888.

The previous prime is 6399859. The next prime is 6399917. The reversal of 6399889 is 9889936.

6399889 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4730625 + 1669264 = 2175^2 + 1292^2 .

It is a cyclic number.

It is not a de Polignac number, because 6399889 - 2⁷ = 6399761 is a prime.

It is not a weakly prime, because it can be changed into another prime (6399829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3199944 + 3199945.

It is an arithmetic number, because the mean of its divisors is an integer number (3199945).

Almost surely, 2^6399889 is an apocalyptic number.

It is an amenable number.

6399889 is a deficient number, since it is larger than the sum of its proper divisors (1).

6399889 is an equidigital number, since it uses as much as digits as its factorization.

6399889 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 839808, while the sum is 52.

The square root of 6399889 is about 2529.8001897383. The cubic root of 6399889 is about 185.6624799709.

The spelling of 6399889 in words is "six million, three hundred ninety-nine thousand, eight hundred eighty-nine".