204839 has 4 divisors (see below), whose sum is σ = 215640. Its totient is φ = 194040.

The previous prime is 204821. The next prime is 204857. The reversal of 204839 is 938402.

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

It is an interprime number because it is at equal distance from previous prime (204821) and next prime (204857).

It is a cyclic number.

It is not a de Polignac number, because 204839 - 2⁸ = 204583 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 (204859) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5372 + ... + 5409.

It is an arithmetic number, because the mean of its divisors is an integer number (53910).

2²⁰⁴⁸³⁹ is an apocalyptic number.

204839 is a deficient number, since it is larger than the sum of its proper divisors (10801).

204839 is a wasteful number, since it uses less digits than its factorization.

204839 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10800.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 204839 is about 452.5914272277. The cubic root of 204839 is about 58.9482453353.

The spelling of 204839 in words is "two hundred four thousand, eight hundred thirty-nine".