204563609 has 2 divisors, whose sum is σ = 204563610. Its totient is φ = 204563608.

The previous prime is 204563551. The next prime is 204563641. The reversal of 204563609 is 906365402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 165688384 + 38875225 = 12872^2 + 6235^2 .

It is a cyclic number.

It is not a de Polignac number, because 204563609 - 2²⁰ = 203515033 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (204563809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102281804 + 102281805.

It is an arithmetic number, because the mean of its divisors is an integer number (102281805).

Almost surely, 2^204563609 is an apocalyptic number.

It is an amenable number.

204563609 is a deficient number, since it is larger than the sum of its proper divisors (1).

204563609 is an equidigital number, since it uses as much as digits as its factorization.

204563609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38880, while the sum is 35.

The square root of 204563609 is about 14302.5735096870. The cubic root of 204563609 is about 589.2181629143.

The spelling of 204563609 in words is "two hundred four million, five hundred sixty-three thousand, six hundred nine".