18908688193 has 2 divisors, whose sum is σ = 18908688194. Its totient is φ = 18908688192.

The previous prime is 18908688187. The next prime is 18908688203. The reversal of 18908688193 is 39188680981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11844621889 + 7064066304 = 108833^2 + 84048^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18908688193 is a prime.

It is not a weakly prime, because it can be changed into another prime (18908688133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9454344096 + 9454344097.

It is an arithmetic number, because the mean of its divisors is an integer number (9454344097).

Almost surely, 2^18908688193 is an apocalyptic number.

It is an amenable number.

18908688193 is a deficient number, since it is larger than the sum of its proper divisors (1).

18908688193 is an equidigital number, since it uses as much as digits as its factorization.

18908688193 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5971968, while the sum is 61.

The spelling of 18908688193 in words is "eighteen billion, nine hundred eight million, six hundred eighty-eight thousand, one hundred ninety-three".