305239 has 4 divisors (see below), whose sum is σ = 333000. Its totient is φ = 277480.

The previous prime is 305237. The next prime is 305243. The reversal of 305239 is 932503.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 305239 - 2¹ = 305237 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (305231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13864 + ... + 13885.

It is an arithmetic number, because the mean of its divisors is an integer number (83250).

2³⁰⁵²³⁹ is an apocalyptic number.

305239 is a deficient number, since it is larger than the sum of its proper divisors (27761).

305239 is a wasteful number, since it uses less digits than its factorization.

305239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27760.

The product of its (nonzero) digits is 810, while the sum is 22.

The square root of 305239 is about 552.4843889197. The cubic root of 305239 is about 67.3307327253.

Subtracting 305239 from its reverse (932503), we obtain a square (627264 = 792²).

The spelling of 305239 in words is "three hundred five thousand, two hundred thirty-nine".