320221320 has 128 divisors (see below), whose sum is σ = 1009152000. Its totient is φ = 81181440.

The previous prime is 320221313. The next prime is 320221327. The reversal of 320221320 is 23122023.

It is an interprime number because it is at equal distance from previous prime (320221313) and next prime (320221327).

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 320221320.

It is not an unprimeable number, because it can be changed into a prime (320221327) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 218751 + ... + 220209.

It is an arithmetic number, because the mean of its divisors is an integer number (7884000).

Almost surely, 2^320221320 is an apocalyptic number.

320221320 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 320221320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (504576000).

320221320 is an abundant number, since it is smaller than the sum of its proper divisors (688930680).

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

320221320 is a wasteful number, since it uses less digits than its factorization.

320221320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1563 (or 1559 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 15.

The square root of 320221320 is about 17894.7288328155. The cubic root of 320221320 is about 684.1480306128.

Adding to 320221320 its reverse (23122023), we get a palindrome (343343343).

The spelling of 320221320 in words is "three hundred twenty million, two hundred twenty-one thousand, three hundred twenty".