240309 has 6 divisors (see below), whose sum is σ = 347126. Its totient is φ = 160200.

The previous prime is 240287. The next prime is 240319. The reversal of 240309 is 903042.

It can be written as a sum of positive squares in only one way, i.e., 152100 + 88209 = 390^2 + 297^2 .

It is not a de Polignac number, because 240309 - 2¹¹ = 238261 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 240291 and 240300.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 240309.

It is not an unprimeable number, because it can be changed into a prime (240319) 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 in 5 ways as a sum of consecutive naturals, for example, 13342 + ... + 13359.

2²⁴⁰³⁰⁹ is an apocalyptic number.

It is an amenable number.

240309 is a deficient number, since it is larger than the sum of its proper divisors (106817).

240309 is a wasteful number, since it uses less digits than its factorization.

240309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26707 (or 26704 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 240309 is about 490.2132189160. The cubic root of 240309 is about 62.1713090935.

The spelling of 240309 in words is "two hundred forty thousand, three hundred nine".