866786278583391 has 16 divisors (see below), whose sum is σ = 1173528171118848. Its totient is φ = 568959241593600.

The previous prime is 866786278583339. The next prime is 866786278583429. The reversal of 866786278583391 is 193385872687668.

866786278583391 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 866786278583391 - 2⁷ = 866786278583263 is a prime.

It is a super-2 number, since 2×866786278583391² (a number of 31 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 866786278583298 and 866786278583307.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866786278582391) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1035710875 + ... + 1036547436.

It is an arithmetic number, because the mean of its divisors is an integer number (73345510694928).

Almost surely, 2^{866786278583391} is an apocalyptic number.

866786278583391 is a deficient number, since it is larger than the sum of its proper divisors (306741892535457).

866786278583391 is a wasteful number, since it uses less digits than its factorization.

866786278583391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2072260462.

The product of its digits is 35115171840, while the sum is 87.

The spelling of 866786278583391 in words is "eight hundred sixty-six trillion, seven hundred eighty-six billion, two hundred seventy-eight million, five hundred eighty-three thousand, three hundred ninety-one".