866686845531 has 16 divisors (see below), whose sum is σ = 1244514569760. Its totient is φ = 533328115200.

The previous prime is 866686845529. The next prime is 866686845539. The reversal of 866686845531 is 135548686668.

It is not a de Polignac number, because 866686845531 - 2¹ = 866686845529 is a prime.

It is a super-2 number, since 2×866686845531² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (866686845539) 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, 880825 + ... + 1584053.

It is an arithmetic number, because the mean of its divisors is an integer number (77782160610).

Almost surely, 2^866686845531 is an apocalyptic number.

866686845531 is a deficient number, since it is larger than the sum of its proper divisors (377827724229).

866686845531 is a wasteful number, since it uses less digits than its factorization.

866686845531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 734846.

The product of its digits is 199065600, while the sum is 66.

The spelling of 866686845531 in words is "eight hundred sixty-six billion, six hundred eighty-six million, eight hundred forty-five thousand, five hundred thirty-one".