243689908289 has 2 divisors, whose sum is σ = 243689908290. Its totient is φ = 243689908288.

The previous prime is 243689908283. The next prime is 243689908339. The reversal of 243689908289 is 982809986342.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 237651375025 + 6038533264 = 487495^2 + 77708^2 .

It is a cyclic number.

It is not a de Polignac number, because 243689908289 - 2¹² = 243689904193 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (243689908283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121844954144 + 121844954145.

It is an arithmetic number, because the mean of its divisors is an integer number (121844954145).

Almost surely, 2^243689908289 is an apocalyptic number.

It is an amenable number.

243689908289 is a deficient number, since it is larger than the sum of its proper divisors (1).

243689908289 is an equidigital number, since it uses as much as digits as its factorization.

243689908289 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 107495424, while the sum is 68.

The spelling of 243689908289 in words is "two hundred forty-three billion, six hundred eighty-nine million, nine hundred eight thousand, two hundred eighty-nine".