309438 has 12 divisors (see below), whose sum is σ = 670488. Its totient is φ = 103140.

The previous prime is 309437. The next prime is 309457. The reversal of 309438 is 834903.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

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

It is a plaindrome in base 13.

It is a zygodrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (309433) 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, 8578 + ... + 8613.

It is an arithmetic number, because the mean of its divisors is an integer number (55874).

2³⁰⁹⁴³⁸ is an apocalyptic number.

309438 is an abundant number, since it is smaller than the sum of its proper divisors (361050).

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

309438 is a wasteful number, since it uses less digits than its factorization.

309438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17199 (or 17196 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 309438 is about 556.2715164378. The cubic root of 309438 is about 67.6380712920.

It can be divided in two parts, 309 and 438, that added together give a palindrome (747).

The spelling of 309438 in words is "three hundred nine thousand, four hundred thirty-eight".