2123211221 has 4 divisors (see below), whose sum is σ = 2234959200. Its totient is φ = 2011463244.

The previous prime is 2123211119. The next prime is 2123211227. The reversal of 2123211221 is 1221123212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2123211221 - 2¹⁰ = 2123210197 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 2123211221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2123211227) 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, 55873961 + ... + 55873998.

It is an arithmetic number, because the mean of its divisors is an integer number (558739800).

Almost surely, 2^2123211221 is an apocalyptic number.

It is an amenable number.

2123211221 is a deficient number, since it is larger than the sum of its proper divisors (111747979).

2123211221 is a wasteful number, since it uses less digits than its factorization.

2123211221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111747978.

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

The square root of 2123211221 is about 46078.3161693220. The cubic root of 2123211221 is about 1285.2799525299.

Adding to 2123211221 its reverse (1221123212), we get a palindrome (3344334433).

The spelling of 2123211221 in words is "two billion, one hundred twenty-three million, two hundred eleven thousand, two hundred twenty-one".