320720 has 40 divisors (see below), whose sum is σ = 788640. Its totient is φ = 120960.

The previous prime is 320713. The next prime is 320741. The reversal of 320720 is 27023.

320720 is nontrivially palindromic in base 14.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×320720² = 205722636800, which contains 22 as substring.

It is an Ulam number.

320720 is a modest number, since divided by 720 gives 320 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 320695 and 320704.

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 320720.

It is an unprimeable number.

320720 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 7 ways as a sum of consecutive naturals, for example, 1415 + ... + 1625.

It is an arithmetic number, because the mean of its divisors is an integer number (19716).

2³²⁰⁷²⁰ 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 320720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (394320).

320720 is an abundant number, since it is smaller than the sum of its proper divisors (467920).

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

320720 is a wasteful number, since it uses less digits than its factorization.

320720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243 (or 237 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 14.

The square root of 320720 is about 566.3214634817. The cubic root of 320720 is about 68.4502987190.

Adding to 320720 its reverse (27023), we get a palindrome (347743).

It can be divided in two parts, 320 and 720, that multiplied together give a square (230400 = 480²).

The spelling of 320720 in words is "three hundred twenty thousand, seven hundred twenty", and thus it is an iban number.