18708668893 has 2 divisors, whose sum is σ = 18708668894. Its totient is φ = 18708668892.

The previous prime is 18708668879. The next prime is 18708668921. The reversal of 18708668893 is 39886680781.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15462176409 + 3246492484 = 124347^2 + 56978^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18708668893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18708668843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9354334446 + 9354334447.

It is an arithmetic number, because the mean of its divisors is an integer number (9354334447).

Almost surely, 2^18708668893 is an apocalyptic number.

It is an amenable number.

18708668893 is a deficient number, since it is larger than the sum of its proper divisors (1).

18708668893 is an equidigital number, since it uses as much as digits as its factorization.

18708668893 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27869184, while the sum is 64.

The spelling of 18708668893 in words is "eighteen billion, seven hundred eight million, six hundred sixty-eight thousand, eight hundred ninety-three".