865885 has 4 divisors (see below), whose sum is σ = 1039068. Its totient is φ = 692704.

The previous prime is 865877. The next prime is 865889. The reversal of 865885 is 588568.

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

It can be written as a sum of positive squares in 2 ways, for example, as 674041 + 191844 = 821^2 + 438^2 .

It is a cyclic number.

It is not a de Polignac number, because 865885 - 2³ = 865877 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 (865889) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86584 + ... + 86593.

It is an arithmetic number, because the mean of its divisors is an integer number (259767).

2⁸⁶⁵⁸⁸⁵ is an apocalyptic number.

It is an amenable number.

865885 is a deficient number, since it is larger than the sum of its proper divisors (173183).

865885 is a wasteful number, since it uses less digits than its factorization.

865885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173182.

The product of its digits is 76800, while the sum is 40.

The square root of 865885 is about 930.5294192018. The cubic root of 865885 is about 95.3132778759.

The spelling of 865885 in words is "eight hundred sixty-five thousand, eight hundred eighty-five".