242307721 has 2 divisors, whose sum is σ = 242307722. Its totient is φ = 242307720.

The previous prime is 242307707. The next prime is 242307733. The reversal of 242307721 is 127703242.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 165482496 + 76825225 = 12864^2 + 8765^2 .

It is a cyclic number.

It is not a de Polignac number, because 242307721 - 2¹⁹ = 241783433 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 242307721.

It is not a weakly prime, because it can be changed into another prime (242307761) 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, 121153860 + 121153861.

It is an arithmetic number, because the mean of its divisors is an integer number (121153861).

Almost surely, 2^242307721 is an apocalyptic number.

It is an amenable number.

242307721 is a deficient number, since it is larger than the sum of its proper divisors (1).

242307721 is an equidigital number, since it uses as much as digits as its factorization.

242307721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4704, while the sum is 28.

The square root of 242307721 is about 15566.2365715031. The cubic root of 242307721 is about 623.4319913680.

The spelling of 242307721 in words is "two hundred forty-two million, three hundred seven thousand, seven hundred twenty-one".