320321131220 has 12 divisors (see below), whose sum is σ = 672674375604. Its totient is φ = 128128452480.

The previous prime is 320321131187. The next prime is 320321131321. The reversal of 320321131220 is 22131123023.

It can be written as a sum of positive squares in 2 ways, for example, as 78284682436 + 242036448784 = 279794^2 + 491972^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 16016056561 = 320321131220 / (3 + 2 + 0 + 3 + 2 + 1 + 1 + 3 + 1 + 2 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 320321131192 and 320321131201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8008028261 + ... + 8008028300.

It is an arithmetic number, because the mean of its divisors is an integer number (56056197967).

Almost surely, 2^320321131220 is an apocalyptic number.

It is an amenable number.

320321131220 is an abundant number, since it is smaller than the sum of its proper divisors (352353244384).

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

320321131220 is a wasteful number, since it uses less digits than its factorization.

320321131220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16016056570 (or 16016056568 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 320321131220 its reverse (22131123023), we get a palindrome (342452254243).

The spelling of 320321131220 in words is "three hundred twenty billion, three hundred twenty-one million, one hundred thirty-one thousand, two hundred twenty".