242509 has 2 divisors, whose sum is σ = 242510.
Its totient is φ = 242508.
The previous prime is 242491. The next prime is 242519. The reversal of 242509 is 905242.
It is a happy number.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 220900 + 21609 = 470^2 + 147^2
It is a cyclic number.
It is not a de Polignac number, because 242509 - 213 = 234317 is a prime.
It is a nialpdrome in base 12.
It is a self number, because there is not a number n which added to its sum of digits gives 242509.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (242519) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (11) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121254 + 121255.
It is an arithmetic number, because the mean of its divisors is an integer number (121255).
2242509 is an apocalyptic number.
It is an amenable number.
242509 is a deficient number, since it is larger than the sum of its proper divisors (1).
242509 is an equidigital number, since it uses as much as digits as its factorization.
242509 is an odious number, because the sum of its binary digits is odd.
The product of its (nonzero) digits is 720, while the sum is 22.
The square root of 242509 is about 492.4520281205.
The cubic root of 242509 is about 62.3604566744.
The spelling of 242509 in words is "two hundred forty-two thousand, five hundred nine".