866509307216 has 80 divisors (see below), whose sum is σ = 1982058759168. Its totient is φ = 359115724800.

The previous prime is 866509307179. The next prime is 866509307221. The reversal of 866509307216 is 612703905668.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4633706 + ... + 4817078.

Almost surely, 2^866509307216 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 866509307216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (991029379584).

866509307216 is an abundant number, since it is smaller than the sum of its proper divisors (1115549451952).

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

866509307216 is a wasteful number, since it uses less digits than its factorization.

866509307216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 184780 (or 184774 counting only the distinct ones).

The product of its (nonzero) digits is 3265920, while the sum is 53.

The spelling of 866509307216 in words is "eight hundred sixty-six billion, five hundred nine million, three hundred seven thousand, two hundred sixteen".