309424 has 20 divisors (see below), whose sum is σ = 609336. Its totient is φ = 152192.

The previous prime is 309403. The next prime is 309433. The reversal of 309424 is 424903.

It is a plaindrome in base 13.

It is a zygodrome in base 13.

It is a junction number, because it is equal to n+sod(n) for n = 309395 and 309404.

It is an unprimeable number.

309424 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1212 + ... + 1444.

2³⁰⁹⁴²⁴ is an apocalyptic number.

It is an amenable number.

309424 is a deficient number, since it is larger than the sum of its proper divisors (299912).

309424 is a wasteful number, since it uses less digits than its factorization.

309424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324 (or 318 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 309424 is about 556.2589325125. The cubic root of 309424 is about 67.6370512198.

The spelling of 309424 in words is "three hundred nine thousand, four hundred twenty-four".