242309 has 2 divisors, whose sum is σ = 242310. Its totient is φ = 242308.

The previous prime is 242279. The next prime is 242329. The reversal of 242309 is 903242.

242309 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (242329) can be obtained adding 242309 to its sum of digits (20).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 240100 + 2209 = 490^2 + 47^2 .

It is a cyclic number.

It is not a de Polignac number, because 242309 - 2¹² = 238213 is a prime.

It is a Chen prime.

It is a plaindrome in base 15.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (242329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121154 + 121155.

It is an arithmetic number, because the mean of its divisors is an integer number (121155).

2²⁴²³⁰⁹ is an apocalyptic number.

It is an amenable number.

242309 is a deficient number, since it is larger than the sum of its proper divisors (1).

242309 is an equidigital number, since it uses as much as digits as its factorization.

242309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 242309 is about 492.2489207708. The cubic root of 242309 is about 62.3433088276.

The spelling of 242309 in words is "two hundred forty-two thousand, three hundred nine".