205343491 has 2 divisors, whose sum is σ = 205343492. Its totient is φ = 205343490.

The previous prime is 205343477. The next prime is 205343497. The reversal of 205343491 is 194343502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 205343491 - 2⁷ = 205343363 is a prime.

It is not a weakly prime, because it can be changed into another prime (205343497) 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, 102671745 + 102671746.

It is an arithmetic number, because the mean of its divisors is an integer number (102671746).

Almost surely, 2^205343491 is an apocalyptic number.

205343491 is a deficient number, since it is larger than the sum of its proper divisors (1).

205343491 is an equidigital number, since it uses as much as digits as its factorization.

205343491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12960, while the sum is 31.

The square root of 205343491 is about 14329.8112688200. The cubic root of 205343491 is about 589.9659953590.

Adding to 205343491 its reverse (194343502), we get a palindrome (399686993).

It can be divided in two parts, 20534 and 3491, that added together give a square (24025 = 155²).

The spelling of 205343491 in words is "two hundred five million, three hundred forty-three thousand, four hundred ninety-one".