309120 has 128 divisors (see below), whose sum is σ = 1175040. Its totient is φ = 67584.

The previous prime is 309109. The next prime is 309121. The reversal of 309120 is 21903.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 309120.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (309121) by changing a digit.

309120 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 15 ways as a sum of consecutive naturals, for example, 13429 + ... + 13451.

It is an arithmetic number, because the mean of its divisors is an integer number (9180).

2³⁰⁹¹²⁰ is an apocalyptic number.

309120 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 309120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (587520).

309120 is an abundant number, since it is smaller than the sum of its proper divisors (865920).

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

309120 is a wasteful number, since it uses less digits than its factorization.

309120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52 (or 40 counting only the distinct ones).

The product of its (nonzero) digits is 54, while the sum is 15.

The square root of 309120 is about 555.9856113246. The cubic root of 309120 is about 67.6148934891.

The spelling of 309120 in words is "three hundred nine thousand, one hundred twenty".