204123559 has 4 divisors (see below), whose sum is σ = 204477904. Its totient is φ = 203769216.

The previous prime is 204123541. The next prime is 204123583. The reversal of 204123559 is 955321402.

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 204123559 - 2⁵ = 204123527 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 204123559.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204123659) 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, 176307 + ... + 177460.

It is an arithmetic number, because the mean of its divisors is an integer number (51119476).

Almost surely, 2^204123559 is an apocalyptic number.

204123559 is a deficient number, since it is larger than the sum of its proper divisors (354345).

204123559 is an equidigital number, since it uses as much as digits as its factorization.

204123559 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 354344.

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 204123559 is about 14287.1816324984. The cubic root of 204123559 is about 588.7953578379.

It can be divided in two parts, 2041 and 23559, that added together give a square (25600 = 160²).

The spelling of 204123559 in words is "two hundred four million, one hundred twenty-three thousand, five hundred fifty-nine".