6399657 has 24 divisors (see below), whose sum is σ = 10183680. Its totient is φ = 3840480.

The previous prime is 6399643. The next prime is 6399677. The reversal of 6399657 is 7569936.

6399657 is a `hidden beast` number, since 639 + 9 + 6 + 5 + 7 = 666.

It is not a de Polignac number, because 6399657 - 2¹⁰ = 6398633 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6399677) 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 in 23 ways as a sum of consecutive naturals, for example, 12319 + ... + 12827.

It is an arithmetic number, because the mean of its divisors is an integer number (424320).

Almost surely, 2^6399657 is an apocalyptic number.

It is an amenable number.

6399657 is a deficient number, since it is larger than the sum of its proper divisors (3784023).

6399657 is a wasteful number, since it uses less digits than its factorization.

6399657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 653 (or 650 counting only the distinct ones).

The product of its digits is 306180, while the sum is 45.

The square root of 6399657 is about 2529.7543358990. The cubic root of 6399657 is about 185.6602364832.

It can be divided in two parts, 6399 and 657, that added together give a square (7056 = 84²).

The spelling of 6399657 in words is "six million, three hundred ninety-nine thousand, six hundred fifty-seven".