18686868679 has 2 divisors, whose sum is σ = 18686868680. Its totient is φ = 18686868678.

The previous prime is 18686868677. The next prime is 18686868691. The reversal of 18686868679 is 97686868681.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18686868679 - 2¹ = 18686868677 is a prime.

It is a super-2 number, since 2×18686868679² (a number of 21 digits) contains 22 as substring.

Together with 18686868677, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18686868671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9343434339 + 9343434340.

It is an arithmetic number, because the mean of its divisors is an integer number (9343434340).

Almost surely, 2^18686868679 is an apocalyptic number.

18686868679 is a deficient number, since it is larger than the sum of its proper divisors (1).

18686868679 is an equidigital number, since it uses as much as digits as its factorization.

18686868679 is an evil number, because the sum of its binary digits is even.

The product of its digits is 334430208, while the sum is 73.

The spelling of 18686868679 in words is "eighteen billion, six hundred eighty-six million, eight hundred sixty-eight thousand, six hundred seventy-nine".