204603661 has 2 divisors, whose sum is σ = 204603662. Its totient is φ = 204603660.

The previous prime is 204603649. The next prime is 204603683. The reversal of 204603661 is 166306402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 184443561 + 20160100 = 13581^2 + 4490^2 .

It is a cyclic number.

It is not a de Polignac number, because 204603661 - 2¹⁷ = 204472589 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (204609661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102301830 + 102301831.

It is an arithmetic number, because the mean of its divisors is an integer number (102301831).

Almost surely, 2^204603661 is an apocalyptic number.

It is an amenable number.

204603661 is a deficient number, since it is larger than the sum of its proper divisors (1).

204603661 is an equidigital number, since it uses as much as digits as its factorization.

204603661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 28.

The square root of 204603661 is about 14303.9736087564. The cubic root of 204603661 is about 589.2566152176.

The spelling of 204603661 in words is "two hundred four million, six hundred three thousand, six hundred sixty-one".