204520 has 16 divisors (see below), whose sum is σ = 460260. Its totient is φ = 81792.

The previous prime is 204517. The next prime is 204521. The reversal of 204520 is 25402.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 171396 + 33124 = 414^2 + 182^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 204520.

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, 2517 + ... + 2596.

2²⁰⁴⁵²⁰ is an apocalyptic number.

204520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

204520 is an abundant number, since it is smaller than the sum of its proper divisors (255740).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

204520 is a wasteful number, since it uses less digits than its factorization.

204520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5124 (or 5120 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 13.

The square root of 204520 is about 452.2388749323. The cubic root of 204520 is about 58.9176289971.

Adding to 204520 its reverse (25402), we get a palindrome (229922).

The spelling of 204520 in words is "two hundred four thousand, five hundred twenty".