866559087 has 16 divisors (see below), whose sum is σ = 1351360000. Its totient is φ = 547300152.

The previous prime is 866559073. The next prime is 866559097. The reversal of 866559087 is 780955668.

866559087 is a `hidden beast` number, since 8 + 6 + 6 + 559 + 0 + 87 = 666.

It is not a de Polignac number, because 866559087 - 2¹⁸ = 866296943 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866559097) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 844087 + ... + 845112.

It is an arithmetic number, because the mean of its divisors is an integer number (84460000).

Almost surely, 2^866559087 is an apocalyptic number.

866559087 is a deficient number, since it is larger than the sum of its proper divisors (484800913).

866559087 is a wasteful number, since it uses less digits than its factorization.

866559087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1689227 (or 1689221 counting only the distinct ones).

The product of its (nonzero) digits is 3628800, while the sum is 54.

The square root of 866559087 is about 29437.3756812662. The cubic root of 866559087 is about 953.3800509188.

The spelling of 866559087 in words is "eight hundred sixty-six million, five hundred fifty-nine thousand, eighty-seven".