6399899 has 4 divisors (see below), whose sum is σ = 6981720. Its totient is φ = 5818080.

The previous prime is 6399889. The next prime is 6399917. The reversal of 6399899 is 9989936.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 6399899 - 2⁸ = 6399643 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6399899.

It is not an unprimeable number, because it can be changed into a prime (6399829) 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 in 3 ways as a sum of consecutive naturals, for example, 290894 + ... + 290915.

It is an arithmetic number, because the mean of its divisors is an integer number (1745430).

Almost surely, 2^6399899 is an apocalyptic number.

6399899 is a deficient number, since it is larger than the sum of its proper divisors (581821).

6399899 is a wasteful number, since it uses less digits than its factorization.

6399899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 581820.

The product of its digits is 944784, while the sum is 53.

The square root of 6399899 is about 2529.8021661782. The cubic root of 6399899 is about 185.6625766717.

The spelling of 6399899 in words is "six million, three hundred ninety-nine thousand, eight hundred ninety-nine".