205123447 has 2 divisors, whose sum is σ = 205123448. Its totient is φ = 205123446.

The previous prime is 205123427. The next prime is 205123481. The reversal of 205123447 is 744321502.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 205123447 - 2⁷ = 205123319 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205123417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102561723 + 102561724.

It is an arithmetic number, because the mean of its divisors is an integer number (102561724).

Almost surely, 2^205123447 is an apocalyptic number.

205123447 is a deficient number, since it is larger than the sum of its proper divisors (1).

205123447 is an equidigital number, since it uses as much as digits as its factorization.

205123447 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6720, while the sum is 28.

The square root of 205123447 is about 14322.1313707143. The cubic root of 205123447 is about 589.7551861839.

Adding to 205123447 its reverse (744321502), we get a palindrome (949444949).

The spelling of 205123447 in words is "two hundred five million, one hundred twenty-three thousand, four hundred forty-seven".