391320 has 48 divisors (see below), whose sum is σ = 1272960. Its totient is φ = 104256.

The previous prime is 391301. The next prime is 391331. The reversal of 391320 is 23193.

391320 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 391293 and 391302.

It is a congruent number.

It is an unprimeable number.

391320 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 11 ways as a sum of consecutive naturals, for example, 184 + ... + 903.

It is an arithmetic number, because the mean of its divisors is an integer number (26520).

2³⁹¹³²⁰ is an apocalyptic number.

391320 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 391320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (636480).

391320 is an abundant number, since it is smaller than the sum of its proper divisors (881640).

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

391320 is a wasteful number, since it uses less digits than its factorization.

391320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1104 (or 1097 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 18.

The square root of 391320 is about 625.5557529110. Note that the first 3 decimals coincide. The cubic root of 391320 is about 73.1437712056.

The spelling of 391320 in words is "three hundred ninety-one thousand, three hundred twenty".