243248261 has 2 divisors, whose sum is σ = 243248262. Its totient is φ = 243248260.

The previous prime is 243248237. The next prime is 243248281. The reversal of 243248261 is 162842342.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 237930625 + 5317636 = 15425^2 + 2306^2 .

It is a cyclic number.

It is not a de Polignac number, because 243248261 - 2⁶ = 243248197 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243248231) 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, 121624130 + 121624131.

It is an arithmetic number, because the mean of its divisors is an integer number (121624131).

Almost surely, 2^243248261 is an apocalyptic number.

It is an amenable number.

243248261 is a deficient number, since it is larger than the sum of its proper divisors (1).

243248261 is an equidigital number, since it uses as much as digits as its factorization.

243248261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18432, while the sum is 32.

The square root of 243248261 is about 15596.4182106021. The cubic root of 243248261 is about 624.2375863923.

The spelling of 243248261 in words is "two hundred forty-three million, two hundred forty-eight thousand, two hundred sixty-one".