18866850017 has 2 divisors, whose sum is σ = 18866850018. Its totient is φ = 18866850016.

The previous prime is 18866850001. The next prime is 18866850043. The reversal of 18866850017 is 71005866881.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17581699216 + 1285150801 = 132596^2 + 35849^2 .

It is a cyclic number.

It is not a de Polignac number, because 18866850017 - 2⁴ = 18866850001 is a prime.

It is not a weakly prime, because it can be changed into another prime (18866850097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9433425008 + 9433425009.

It is an arithmetic number, because the mean of its divisors is an integer number (9433425009).

Almost surely, 2^18866850017 is an apocalyptic number.

It is an amenable number.

18866850017 is a deficient number, since it is larger than the sum of its proper divisors (1).

18866850017 is an equidigital number, since it uses as much as digits as its factorization.

18866850017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 645120, while the sum is 50.

The spelling of 18866850017 in words is "eighteen billion, eight hundred sixty-six million, eight hundred fifty thousand, seventeen".