6689647 has 4 divisors (see below), whose sum is σ = 6781360. Its totient is φ = 6597936.

The previous prime is 6689629. The next prime is 6689659. The reversal of 6689647 is 7469866.

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 6689647 - 2¹⁵ = 6656879 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6689597 and 6689606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6689047) 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, 45747 + ... + 45892.

It is an arithmetic number, because the mean of its divisors is an integer number (1695340).

Almost surely, 2^6689647 is an apocalyptic number.

6689647 is a deficient number, since it is larger than the sum of its proper divisors (91713).

6689647 is an equidigital number, since it uses as much as digits as its factorization.

6689647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91712.

The product of its digits is 435456, while the sum is 46.

The square root of 6689647 is about 2586.4351915329. The cubic root of 6689647 is about 188.4232109886.

The spelling of 6689647 in words is "six million, six hundred eighty-nine thousand, six hundred forty-seven".