6678691 has 2 divisors, whose sum is σ = 6678692. Its totient is φ = 6678690.

The previous prime is 6678667. The next prime is 6678701. The reversal of 6678691 is 1968766.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6678691 - 2¹⁵ = 6645923 is a prime.

It is not a weakly prime, because it can be changed into another prime (6678641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3339345 + 3339346.

It is an arithmetic number, because the mean of its divisors is an integer number (3339346).

Almost surely, 2^6678691 is an apocalyptic number.

6678691 is a deficient number, since it is larger than the sum of its proper divisors (1).

6678691 is an equidigital number, since it uses as much as digits as its factorization.

6678691 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108864, while the sum is 43.

The square root of 6678691 is about 2584.3163506042. The cubic root of 6678691 is about 188.3202911235.

The spelling of 6678691 in words is "six million, six hundred seventy-eight thousand, six hundred ninety-one".