243340213 has 2 divisors, whose sum is σ = 243340214. Its totient is φ = 243340212.

The previous prime is 243340187. The next prime is 243340267. The reversal of 243340213 is 312043342.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 191600964 + 51739249 = 13842^2 + 7193^2 .

It is a cyclic number.

It is not a de Polignac number, because 243340213 - 2¹³ = 243332021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243340283) 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, 121670106 + 121670107.

It is an arithmetic number, because the mean of its divisors is an integer number (121670107).

Almost surely, 2^243340213 is an apocalyptic number.

It is an amenable number.

243340213 is a deficient number, since it is larger than the sum of its proper divisors (1).

243340213 is an equidigital number, since it uses as much as digits as its factorization.

243340213 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 22.

The square root of 243340213 is about 15599.3657883902. The cubic root of 243340213 is about 624.3162339752.

Adding to 243340213 its reverse (312043342), we get a palindrome (555383555).

The spelling of 243340213 in words is "two hundred forty-three million, three hundred forty thousand, two hundred thirteen".