239509 has 2 divisors, whose sum is σ = 239510. Its totient is φ = 239508.

The previous prime is 239489. The next prime is 239521. The reversal of 239509 is 905932.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 228484 + 11025 = 478^2 + 105^2 .

It is a cyclic number.

It is not a de Polignac number, because 239509 - 2¹³ = 231317 is a prime.

It is a super-2 number, since 2×239509² = 114729122162, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (239539) 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, 119754 + 119755.

It is an arithmetic number, because the mean of its divisors is an integer number (119755).

2²³⁹⁵⁰⁹ is an apocalyptic number.

It is an amenable number.

239509 is a deficient number, since it is larger than the sum of its proper divisors (1).

239509 is an equidigital number, since it uses as much as digits as its factorization.

239509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2430, while the sum is 28.

The square root of 239509 is about 489.3965672131. The cubic root of 239509 is about 62.1022419870.

The spelling of 239509 in words is "two hundred thirty-nine thousand, five hundred nine".