866788517312171 has 2 divisors, whose sum is σ = 866788517312172. Its totient is φ = 866788517312170.

The previous prime is 866788517312141. The next prime is 866788517312197. The reversal of 866788517312171 is 171213715887668.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-866788517312171 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 866788517312095 and 866788517312104.

It is not a weakly prime, because it can be changed into another prime (866788517312141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433394258656085 + 433394258656086.

It is an arithmetic number, because the mean of its divisors is an integer number (433394258656086).

Almost surely, 2^{866788517312171} is an apocalyptic number.

866788517312171 is a deficient number, since it is larger than the sum of its proper divisors (1).

866788517312171 is an equidigital number, since it uses as much as digits as its factorization.

866788517312171 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 189665280, while the sum is 71.

The spelling of 866788517312171 in words is "eight hundred sixty-six trillion, seven hundred eighty-eight billion, five hundred seventeen million, three hundred twelve thousand, one hundred seventy-one".