2221321320 has 224 divisors, whose sum is σ = 7936098120. Its totient is φ = 557383680.

The previous prime is 2221321309. The next prime is 2221321321. The reversal of 2221321320 is 231231222.

2221321320 is a `hidden beast` number, since 2 + 2 + 21 + 321 + 320 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 2161692036 + 59629284 = 46494^2 + 7722^2 .

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 = 2221321293 and 2221321302.

It is not an unprimeable number, because it can be changed into a prime (2221321321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 493480 + ... + 497960.

Almost surely, 2^2221321320 is an apocalyptic number.

2221321320 is a gapful number since it is divisible by the number (20) 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 2221321320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3968049060).

2221321320 is an abundant number, since it is smaller than the sum of its proper divisors (5714776800).

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

2221321320 is a wasteful number, since it uses less digits than its factorization.

2221321320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4527 (or 4508 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 2221321320 is about 47130.8955993836. The cubic root of 2221321320 is about 1304.7795109058.

Adding to 2221321320 its reverse (231231222), we get a palindrome (2452552542).

The spelling of 2221321320 in words is "two billion, two hundred twenty-one million, three hundred twenty-one thousand, three hundred twenty".