204689 has 4 divisors (see below), whose sum is σ = 207360. Its totient is φ = 202020.

The previous prime is 204679. The next prime is 204707. The reversal of 204689 is 986402.

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, and also an emirpimes, since its reverse is a distinct semiprime: 986402 = 2 ⋅493201.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-204689 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (204679) 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, 1217 + ... + 1374.

It is an arithmetic number, because the mean of its divisors is an integer number (51840).

2²⁰⁴⁶⁸⁹ is an apocalyptic number.

It is an amenable number.

204689 is a deficient number, since it is larger than the sum of its proper divisors (2671).

204689 is an equidigital number, since it uses as much as digits as its factorization.

204689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2670.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 204689 is about 452.4256845052. The cubic root of 204689 is about 58.9338529002.

The spelling of 204689 in words is "two hundred four thousand, six hundred eighty-nine".