866587 has 4 divisors (see below), whose sum is σ = 868680. Its totient is φ = 864496.

The previous prime is 866581. The next prime is 866623. The reversal of 866587 is 785668.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 866587 - 2¹⁹ = 342299 is a prime.

It is a pancake number, because a pancake can be divided into 866587 parts by 1316 straight cuts.

It is a Duffinian number.

866587 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (866581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 193 + ... + 1330.

It is an arithmetic number, because the mean of its divisors is an integer number (217170).

2⁸⁶⁶⁵⁸⁷ is an apocalyptic number.

866587 is a deficient number, since it is larger than the sum of its proper divisors (2093).

866587 is a wasteful number, since it uses less digits than its factorization.

866587 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2092.

The product of its digits is 80640, while the sum is 40.

The square root of 866587 is about 930.9065474042. The cubic root of 866587 is about 95.3390287348.

It can be divided in two parts, 86658 and 7, that multiplied together give a palindrome (606606).

The spelling of 866587 in words is "eight hundred sixty-six thousand, five hundred eighty-seven".