6686511679 has 2 divisors, whose sum is σ = 6686511680. Its totient is φ = 6686511678.

The previous prime is 6686511589. The next prime is 6686511703. The reversal of 6686511679 is 9761156866.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6686511679 - 2¹³ = 6686503487 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6686541679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3343255839 + 3343255840.

It is an arithmetic number, because the mean of its divisors is an integer number (3343255840).

Almost surely, 2^6686511679 is an apocalyptic number.

6686511679 is a deficient number, since it is larger than the sum of its proper divisors (1).

6686511679 is an equidigital number, since it uses as much as digits as its factorization.

6686511679 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3265920, while the sum is 55.

The square root of 6686511679 is about 81771.0931747889. The cubic root of 6686511679 is about 1883.9376949651.

The spelling of 6686511679 in words is "six billion, six hundred eighty-six million, five hundred eleven thousand, six hundred seventy-nine".