309680 has 60 divisors (see below), whose sum is σ = 848160. Its totient is φ = 104832.

The previous prime is 309677. The next prime is 309707. The reversal of 309680 is 86903.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3881 + ... + 3959.

It is an arithmetic number, because the mean of its divisors is an integer number (14136).

2³⁰⁹⁶⁸⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 309680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (424080).

309680 is an abundant number, since it is smaller than the sum of its proper divisors (538480).

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

309680 is a wasteful number, since it uses less digits than its factorization.

309680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106 (or 93 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 309680 is about 556.4889936019. The cubic root of 309680 is about 67.6556991076.

It can be divided in two parts, 309 and 680, that added together give a palindrome (989).

The spelling of 309680 in words is "three hundred nine thousand, six hundred eighty".