864809 has 8 divisors (see below), whose sum is σ = 976320. Its totient is φ = 758800.

The previous prime is 864803. The next prime is 864811. The reversal of 864809 is 908468.

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

It is a cyclic number.

It is not a de Polignac number, because 864809 - 2⁴ = 864793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (864803) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1037 + ... + 1674.

It is an arithmetic number, because the mean of its divisors is an integer number (122040).

2⁸⁶⁴⁸⁰⁹ is an apocalyptic number.

It is an amenable number.

864809 is a deficient number, since it is larger than the sum of its proper divisors (111511).

864809 is a wasteful number, since it uses less digits than its factorization.

864809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2751.

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 864809 is about 929.9510739819. The cubic root of 864809 is about 95.2737808690.

The spelling of 864809 in words is "eight hundred sixty-four thousand, eight hundred nine".