2121221320 has 64 divisors (see below), whose sum is σ = 4862300400. Its totient is φ = 832634880.

The previous prime is 2121221303. The next prime is 2121221339. The reversal of 2121221320 is 231221212.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 111133764 + 2010087556 = 10542^2 + 44834^2 .

It is a junction number, because it is equal to n+sod(n) for n = 2121221294 and 2121221303.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1504776 + ... + 1506184.

Almost surely, 2^2121221320 is an apocalyptic number.

2121221320 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 2121221320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2431150200).

2121221320 is an abundant number, since it is smaller than the sum of its proper divisors (2741079080).

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

2121221320 is a wasteful number, since it uses less digits than its factorization.

2121221320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2098 (or 2094 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 2121221320 is about 46056.7185109838. The cubic root of 2121221320 is about 1284.8783000310.

Adding to 2121221320 its reverse (231221212), we get a palindrome (2352442532).

The spelling of 2121221320 in words is "two billion, one hundred twenty-one million, two hundred twenty-one thousand, three hundred twenty".