6686689 has 4 divisors (see below), whose sum is σ = 7038640. Its totient is φ = 6334740.

The previous prime is 6686681. The next prime is 6686699. The reversal of 6686689 is 9866866.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6686689 - 2³ = 6686681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6686681) 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 3 ways as a sum of consecutive naturals, for example, 175947 + ... + 175984.

It is an arithmetic number, because the mean of its divisors is an integer number (1759660).

Almost surely, 2^6686689 is an apocalyptic number.

It is an amenable number.

6686689 is a deficient number, since it is larger than the sum of its proper divisors (351951).

6686689 is a wasteful number, since it uses less digits than its factorization.

6686689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 351950.

The product of its digits is 746496, while the sum is 49.

The square root of 6686689 is about 2585.8632987844. The cubic root of 6686689 is about 188.3954348330.

The spelling of 6686689 in words is "six million, six hundred eighty-six thousand, six hundred eighty-nine".