866786513765989 has 2 divisors, whose sum is σ = 866786513765990. Its totient is φ = 866786513765988.

The previous prime is 866786513765941. The next prime is 866786513765999. The reversal of 866786513765989 is 989567315687668.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 844247358724225 + 22539155041764 = 29055935^2 + 4747542^2 .

It is a cyclic number.

It is not a de Polignac number, because 866786513765989 - 2¹³ = 866786513757797 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 866786513765897 and 866786513765906.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (866786513765999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433393256882994 + 433393256882995.

It is an arithmetic number, because the mean of its divisors is an integer number (433393256882995).

Almost surely, 2^{866786513765989} is an apocalyptic number.

It is an amenable number.

866786513765989 is a deficient number, since it is larger than the sum of its proper divisors (1).

866786513765989 is an equidigital number, since it uses as much as digits as its factorization.

866786513765989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 197522841600, while the sum is 94.

The spelling of 866786513765989 in words is "eight hundred sixty-six trillion, seven hundred eighty-six billion, five hundred thirteen million, seven hundred sixty-five thousand, nine hundred eighty-nine".