205540207 has 2 divisors, whose sum is σ = 205540208. Its totient is φ = 205540206.

The previous prime is 205540193. The next prime is 205540267. The reversal of 205540207 is 702045502.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 205540207 - 2⁷ = 205540079 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205540267) 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, 102770103 + 102770104.

It is an arithmetic number, because the mean of its divisors is an integer number (102770104).

Almost surely, 2^205540207 is an apocalyptic number.

205540207 is a deficient number, since it is larger than the sum of its proper divisors (1).

205540207 is an equidigital number, since it uses as much as digits as its factorization.

205540207 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2800, while the sum is 25.

The square root of 205540207 is about 14336.6734984096. The cubic root of 205540207 is about 590.1543281049.

Adding to 205540207 its reverse (702045502), we get a palindrome (907585709).

The spelling of 205540207 in words is "two hundred five million, five hundred forty thousand, two hundred seven".