866985887 has 16 divisors (see below), whose sum is σ = 907713600. Its totient is φ = 827304192.

The previous prime is 866985883. The next prime is 866985913. The reversal of 866985887 is 788589668.

It is a cyclic number.

It is not a de Polignac number, because 866985887 - 2² = 866985883 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866985883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 536693 + ... + 538305.

It is an arithmetic number, because the mean of its divisors is an integer number (56732100).

Almost surely, 2^866985887 is an apocalyptic number.

866985887 is a deficient number, since it is larger than the sum of its proper divisors (40727713).

866985887 is a wasteful number, since it uses less digits than its factorization.

866985887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1922.

The product of its digits is 46448640, while the sum is 65.

The square root of 866985887 is about 29444.6240763913. The cubic root of 866985887 is about 953.5365456604.

The spelling of 866985887 in words is "eight hundred sixty-six million, nine hundred eighty-five thousand, eight hundred eighty-seven".