865986 has 16 divisors (see below), whose sum is σ = 1889568. Its totient is φ = 262400.

The previous prime is 865979. The next prime is 865993. The reversal of 865986 is 689568.

865986 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (865979) and next prime (865993).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6495 + ... + 6626.

It is an arithmetic number, because the mean of its divisors is an integer number (118098).

2⁸⁶⁵⁹⁸⁶ is an apocalyptic number.

865986 is an abundant number, since it is smaller than the sum of its proper divisors (1023582).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

865986 is a wasteful number, since it uses less digits than its factorization.

865986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13137.

The product of its digits is 103680, while the sum is 42.

The square root of 865986 is about 930.5836878003. The cubic root of 865986 is about 95.3169836286.

The spelling of 865986 in words is "eight hundred sixty-five thousand, nine hundred eighty-six".