6688591 has 16 divisors (see below), whose sum is σ = 8501248. Its totient is φ = 5119200.

The previous prime is 6688579. The next prime is 6688603. The reversal of 6688591 is 1958866.

It is an interprime number because it is at equal distance from previous prime (6688579) and next prime (6688603).

It is a cyclic number.

It is not a de Polignac number, because 6688591 - 2⁵ = 6688559 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6688501) 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 15 ways as a sum of consecutive naturals, for example, 1636 + ... + 4006.

It is an arithmetic number, because the mean of its divisors is an integer number (531328).

Almost surely, 2^6688591 is an apocalyptic number.

6688591 is a deficient number, since it is larger than the sum of its proper divisors (1812657).

6688591 is a wasteful number, since it uses less digits than its factorization.

6688591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2422.

The product of its digits is 103680, while the sum is 43.

The square root of 6688591 is about 2586.2310414965. The cubic root of 6688591 is about 188.4132958974.

The spelling of 6688591 in words is "six million, six hundred eighty-eight thousand, five hundred ninety-one".