204539905 has 4 divisors (see below), whose sum is σ = 245447892. Its totient is φ = 163631920.

The previous prime is 204539887. The next prime is 204539957. The reversal of 204539905 is 509935402.

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 106688241 + 97851664 = 10329^2 + 9892^2 .

It is not a de Polignac number, because 204539905 - 2²⁷ = 70322177 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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, 20453986 + ... + 20453995.

It is an arithmetic number, because the mean of its divisors is an integer number (61361973).

Almost surely, 2^204539905 is an apocalyptic number.

It is an amenable number.

204539905 is a deficient number, since it is larger than the sum of its proper divisors (40907987).

204539905 is an equidigital number, since it uses as much as digits as its factorization.

204539905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40907986.

The product of its (nonzero) digits is 48600, while the sum is 37.

The square root of 204539905 is about 14301.7448236220. The cubic root of 204539905 is about 589.1954032995.

The spelling of 204539905 in words is "two hundred four million, five hundred thirty-nine thousand, nine hundred five".