309432 has 16 divisors (see below), whose sum is σ = 773640. Its totient is φ = 103136.

The previous prime is 309403. The next prime is 309433. The reversal of 309432 is 234903.

It is an alternating number because its digits alternate between odd and even.

It is a junction number, because it is equal to n+sod(n) for n = 309399 and 309408.

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 309432.

It is not an unprimeable number, because it can be changed into a prime (309433) 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, 6423 + ... + 6470.

2³⁰⁹⁴³² is an apocalyptic number.

It is an amenable number.

309432 is an abundant number, since it is smaller than the sum of its proper divisors (464208).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

309432 is a wasteful number, since it uses less digits than its factorization.

309432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12902 (or 12898 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 21.

The square root of 309432 is about 556.2661233618. The cubic root of 309432 is about 67.6376341220.

Subtracting from 309432 its reverse (234903), we obtain a square (74529 = 273²).

It can be divided in two parts, 309 and 432, that added together give a triangular number (741 = T₃₈).

The spelling of 309432 in words is "three hundred nine thousand, four hundred thirty-two".