204523 has 4 divisors (see below), whose sum is σ = 223128. Its totient is φ = 185920.

The previous prime is 204521. The next prime is 204557. The reversal of 204523 is 325402.

204523 is nontrivially palindromic in base 13.

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

It is a cyclic number.

It is not a de Polignac number, because 204523 - 2¹ = 204521 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 204497 and 204506.

It is not an unprimeable number, because it can be changed into a prime (204521) 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, 9286 + ... + 9307.

It is an arithmetic number, because the mean of its divisors is an integer number (55782).

2²⁰⁴⁵²³ is an apocalyptic number.

204523 is a deficient number, since it is larger than the sum of its proper divisors (18605).

204523 is a wasteful number, since it uses less digits than its factorization.

204523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18604.

The product of its (nonzero) digits is 240, while the sum is 16.

The square root of 204523 is about 452.2421917513. The cubic root of 204523 is about 58.9179170733.

Adding to 204523 its reverse (325402), we get a palindrome (529925).

It can be divided in two parts, 204 and 523, that added together give a palindrome (727).

The spelling of 204523 in words is "two hundred four thousand, five hundred twenty-three".