2121220120221 has 12 divisors (see below), whose sum is σ = 3162822832000. Its totient is φ = 1368529109640.

The previous prime is 2121220120177. The next prime is 2121220120267. The reversal of 2121220120221 is 1220210221212.

It is a happy number.

2121220120221 is a `hidden beast` number, since 212 + 1 + 220 + 12 + 0 + 221 = 666.

It is not a de Polignac number, because 2121220120221 - 2¹⁹ = 2121219595933 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2121220120194 and 2121220120203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121220120421) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3801469471 + ... + 3801470028.

Almost surely, 2^{2121220120221} is an apocalyptic number.

It is an amenable number.

2121220120221 is a deficient number, since it is larger than the sum of its proper divisors (1041602711779).

2121220120221 is a wasteful number, since it uses less digits than its factorization.

2121220120221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7602939536 (or 7602939533 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 2121220120221 its reverse (1220210221212), we get a palindrome (3341430341433).

The spelling of 2121220120221 in words is "two trillion, one hundred twenty-one billion, two hundred twenty million, one hundred twenty thousand, two hundred twenty-one".