2123221321 has 4 divisors (see below), whose sum is σ = 2286546052. Its totient is φ = 1959896592.

The previous prime is 2123221267. The next prime is 2123221351. The reversal of 2123221321 is 1231223212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 982132921 + 1141088400 = 31339^2 + 33780^2 .

It is a cyclic number.

It is not a de Polignac number, because 2123221321 - 2⁹ = 2123220809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2123221351) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 81662346 + ... + 81662371.

It is an arithmetic number, because the mean of its divisors is an integer number (571636513).

Almost surely, 2^2123221321 is an apocalyptic number.

It is an amenable number.

2123221321 is a deficient number, since it is larger than the sum of its proper divisors (163324731).

2123221321 is a wasteful number, since it uses less digits than its factorization.

2123221321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163324730.

The product of its digits is 288, while the sum is 19.

The square root of 2123221321 is about 46078.4257652103. The cubic root of 2123221321 is about 1285.2819905289.

Adding to 2123221321 its reverse (1231223212), we get a palindrome (3354444533).

The spelling of 2123221321 in words is "two billion, one hundred twenty-three million, two hundred twenty-one thousand, three hundred twenty-one".