205345321 has 2 divisors, whose sum is σ = 205345322. Its totient is φ = 205345320.

The previous prime is 205345319. The next prime is 205345367. The reversal of 205345321 is 123543502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 130782096 + 74563225 = 11436^2 + 8635^2 .

It is a cyclic number.

It is not a de Polignac number, because 205345321 - 2¹ = 205345319 is a prime.

Together with 205345319, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (205345381) 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, 102672660 + 102672661.

It is an arithmetic number, because the mean of its divisors is an integer number (102672661).

Almost surely, 2^205345321 is an apocalyptic number.

It is an amenable number.

205345321 is a deficient number, since it is larger than the sum of its proper divisors (1).

205345321 is an equidigital number, since it uses as much as digits as its factorization.

205345321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3600, while the sum is 25.

The square root of 205345321 is about 14329.8751215773. The cubic root of 205345321 is about 589.9677479258.

Adding to 205345321 its reverse (123543502), we get a palindrome (328888823).

It can be divided in two parts, 2053 and 45321, that added together give a palindrome (47374).

The spelling of 205345321 in words is "two hundred five million, three hundred forty-five thousand, three hundred twenty-one".