864389 has 4 divisors (see below), whose sum is σ = 869856. Its totient is φ = 858924.

The previous prime is 864379. The next prime is 864407. The reversal of 864389 is 983468.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-864389 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 (864319) 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, 2489 + ... + 2814.

It is an arithmetic number, because the mean of its divisors is an integer number (217464).

2⁸⁶⁴³⁸⁹ is an apocalyptic number.

It is an amenable number.

864389 is a deficient number, since it is larger than the sum of its proper divisors (5467).

864389 is a wasteful number, since it uses less digits than its factorization.

864389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5466.

The product of its digits is 41472, while the sum is 38.

The square root of 864389 is about 929.7252282261. The cubic root of 864389 is about 95.2583549320.

The spelling of 864389 in words is "eight hundred sixty-four thousand, three hundred eighty-nine".