3221121221 has 4 divisors (see below), whose sum is σ = 3221348844. Its totient is φ = 3220893600.

The previous prime is 3221121209. The next prime is 3221121229. The reversal of 3221121221 is 1221211223.

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 777796321 + 2443324900 = 27889^2 + 49430^2 .

It is a cyclic number.

It is not a de Polignac number, because 3221121221 - 2¹⁰ = 3221120197 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3221121221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3221121229) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 91070 + ... + 121391.

It is an arithmetic number, because the mean of its divisors is an integer number (805337211).

Almost surely, 2^3221121221 is an apocalyptic number.

It is an amenable number.

3221121221 is a deficient number, since it is larger than the sum of its proper divisors (227623).

3221121221 is a wasteful number, since it uses less digits than its factorization.

3221121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227622.

The product of its digits is 96, while the sum is 17.

The square root of 3221121221 is about 56754.9224384987. The cubic root of 3221121221 is about 1476.8476275321.

Adding to 3221121221 its reverse (1221211223), we get a palindrome (4442332444).

The spelling of 3221121221 in words is "three billion, two hundred twenty-one million, one hundred twenty-one thousand, two hundred twenty-one".