865439 has 4 divisors (see below), whose sum is σ = 878424. Its totient is φ = 852456.

The previous prime is 865409. The next prime is 865457. The reversal of 865439 is 934568.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-865439 is a prime.

It is a Duffinian number.

It is a plaindrome in base 12.

It is a junction number, because it is equal to n+sod(n) for n = 865399 and 865408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (865409) 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, 6392 + ... + 6525.

It is an arithmetic number, because the mean of its divisors is an integer number (219606).

2⁸⁶⁵⁴³⁹ is an apocalyptic number.

865439 is a deficient number, since it is larger than the sum of its proper divisors (12985).

865439 is a wasteful number, since it uses less digits than its factorization.

865439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12984.

The product of its digits is 25920, while the sum is 35.

The square root of 865439 is about 930.2897398123. The cubic root of 865439 is about 95.2969104127.

The spelling of 865439 in words is "eight hundred sixty-five thousand, four hundred thirty-nine".