866444204172017 has 4 divisors (see below), whose sum is σ = 894394017209856. Its totient is φ = 838494391134180.

The previous prime is 866444204171989. The next prime is 866444204172023. The reversal of 866444204172017 is 710271402444668.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 866444204172017 - 2⁴⁸ = 584969227461361 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (866444204172317) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13974906518873 + ... + 13974906518934.

It is an arithmetic number, because the mean of its divisors is an integer number (223598504302464).

Almost surely, 2^{866444204172017} is an apocalyptic number.

It is an amenable number.

866444204172017 is a deficient number, since it is larger than the sum of its proper divisors (27949813037839).

866444204172017 is a wasteful number, since it uses less digits than its factorization.

866444204172017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27949813037838.

The product of its (nonzero) digits is 14450688, while the sum is 56.

The spelling of 866444204172017 in words is "eight hundred sixty-six trillion, four hundred forty-four billion, two hundred four million, one hundred seventy-two thousand, seventeen".