205205543 has 2 divisors, whose sum is σ = 205205544. Its totient is φ = 205205542.

The previous prime is 205205509. The next prime is 205205551. The reversal of 205205543 is 345502502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 205205543 - 2¹⁸ = 204943399 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205205573) 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, 102602771 + 102602772.

It is an arithmetic number, because the mean of its divisors is an integer number (102602772).

Almost surely, 2^205205543 is an apocalyptic number.

205205543 is a deficient number, since it is larger than the sum of its proper divisors (1).

205205543 is an equidigital number, since it uses as much as digits as its factorization.

205205543 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6000, while the sum is 26.

The square root of 205205543 is about 14324.9971378706. The cubic root of 205205543 is about 589.8338543952.

The spelling of 205205543 in words is "two hundred five million, two hundred five thousand, five hundred forty-three".