866805 has 8 divisors (see below), whose sum is σ = 1386912. Its totient is φ = 462288.

The previous prime is 866783. The next prime is 866819. The reversal of 866805 is 508668.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 866805 - 2⁹ = 866293 is a prime.

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28879 + ... + 28908.

It is an arithmetic number, because the mean of its divisors is an integer number (173364).

2⁸⁶⁶⁸⁰⁵ is an apocalyptic number.

It is an amenable number.

866805 is a deficient number, since it is larger than the sum of its proper divisors (520107).

866805 is a wasteful number, since it uses less digits than its factorization.

866805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57795.

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 866805 is about 931.0236302049. The cubic root of 866805 is about 95.3470226103.

The spelling of 866805 in words is "eight hundred sixty-six thousand, eight hundred five".