6688091 has 4 divisors (see below), whose sum is σ = 6843672. Its totient is φ = 6532512.

The previous prime is 6688079. The next prime is 6688093. The reversal of 6688091 is 1908866.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1908866 = 2 ⋅954433.

It is a cyclic number.

It is not a de Polignac number, because 6688091 - 2⁶ = 6688027 is a prime.

It is a super-2 number, since 2×6688091² = 89461122448562, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6688093) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 77726 + ... + 77811.

It is an arithmetic number, because the mean of its divisors is an integer number (1710918).

Almost surely, 2^6688091 is an apocalyptic number.

6688091 is a deficient number, since it is larger than the sum of its proper divisors (155581).

6688091 is a wasteful number, since it uses less digits than its factorization.

6688091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155580.

The product of its (nonzero) digits is 20736, while the sum is 38.

The square root of 6688091 is about 2586.1343739257. The cubic root of 6688091 is about 188.4086008878.

The spelling of 6688091 in words is "six million, six hundred eighty-eight thousand, ninety-one".