866087765871 has 16 divisors (see below), whose sum is σ = 1155917245440. Its totient is φ = 576825350400.

The previous prime is 866087765863. The next prime is 866087765897. The reversal of 866087765871 is 178567780668.

It is not a de Polignac number, because 866087765871 - 2³ = 866087765863 is a prime.

It is a super-2 number, since 2×866087765871² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 866087765796 and 866087765805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866087765171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12860575 + ... + 12927743.

It is an arithmetic number, because the mean of its divisors is an integer number (72244827840).

Almost surely, 2^866087765871 is an apocalyptic number.

866087765871 is a deficient number, since it is larger than the sum of its proper divisors (289829479569).

866087765871 is a wasteful number, since it uses less digits than its factorization.

866087765871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71326.

The product of its (nonzero) digits is 189665280, while the sum is 69.

The spelling of 866087765871 in words is "eight hundred sixty-six billion, eighty-seven million, seven hundred sixty-five thousand, eight hundred seventy-one".