204672661 has 2 divisors, whose sum is σ = 204672662. Its totient is φ = 204672660.

The previous prime is 204672659. The next prime is 204672683. The reversal of 204672661 is 166276402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 204661636 + 11025 = 14306^2 + 105^2 .

It is a cyclic number.

It is not a de Polignac number, because 204672661 - 2¹ = 204672659 is a prime.

Together with 204672659, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (204672761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102336330 + 102336331.

It is an arithmetic number, because the mean of its divisors is an integer number (102336331).

Almost surely, 2^204672661 is an apocalyptic number.

It is an amenable number.

204672661 is a deficient number, since it is larger than the sum of its proper divisors (1).

204672661 is an equidigital number, since it uses as much as digits as its factorization.

204672661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24192, while the sum is 34.

The square root of 204672661 is about 14306.3853226453. The cubic root of 204672661 is about 589.3228475561.

The spelling of 204672661 in words is "two hundred four million, six hundred seventy-two thousand, six hundred sixty-one".