866511508645518 has 16 divisors (see below), whose sum is σ = 1733024053099776. Its totient is φ = 288836996913720.

The previous prime is 866511508645511. The next prime is 866511508645529. The reversal of 866511508645518 is 815546805115668.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866511508645511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32064088 + ... + 52546443.

It is an arithmetic number, because the mean of its divisors is an integer number (108314003318736).

Almost surely, 2^{866511508645518} is an apocalyptic number.

866511508645518 is an abundant number, since it is smaller than the sum of its proper divisors (866512544454258).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

866511508645518 is a wasteful number, since it uses less digits than its factorization.

866511508645518 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86317399.

The product of its (nonzero) digits is 276480000, while the sum is 69.

The spelling of 866511508645518 in words is "eight hundred sixty-six trillion, five hundred eleven billion, five hundred eight million, six hundred forty-five thousand, five hundred eighteen".