204745 has 4 divisors (see below), whose sum is σ = 245700. Its totient is φ = 163792.

The previous prime is 204733. The next prime is 204749. The reversal of 204745 is 547402.

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

It can be written as a sum of positive squares in 2 ways, for example, as 82944 + 121801 = 288^2 + 349^2 .

It is a cyclic number.

It is not a de Polignac number, because 204745 - 2⁹ = 204233 is a prime.

It is not an unprimeable number, because it can be changed into a prime (204749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20470 + ... + 20479.

It is an arithmetic number, because the mean of its divisors is an integer number (61425).

2²⁰⁴⁷⁴⁵ is an apocalyptic number.

It is an amenable number.

204745 is a deficient number, since it is larger than the sum of its proper divisors (40955).

204745 is an equidigital number, since it uses as much as digits as its factorization.

204745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40954.

The product of its (nonzero) digits is 1120, while the sum is 22.

The square root of 204745 is about 452.4875688900. The cubic root of 204745 is about 58.9392268982.

It can be divided in two parts, 204 and 745, that added together give a palindrome (949).

The spelling of 204745 in words is "two hundred four thousand, seven hundred forty-five".