21220120211121 has 24 divisors (see below), whose sum is σ = 33473992458816. Its totient is φ = 12874612474080.

The previous prime is 21220120211093. The next prime is 21220120211123. The reversal of 21220120211121 is 12111202102212.

21220120211121 is a `hidden beast` number, since 212 + 2 + 0 + 120 + 211 + 121 = 666.

It is not a de Polignac number, because 21220120211121 - 2¹⁴ = 21220120194737 is a prime.

It is a super-2 number, since 2×21220120211121² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21220120211094 and 21220120211103.

It is not an unprimeable number, because it can be changed into a prime (21220120211123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1277234995 + ... + 1277251608.

It is an arithmetic number, because the mean of its divisors is an integer number (1394749685784).

Almost surely, 2^{21220120211121} is an apocalyptic number.

It is an amenable number.

21220120211121 is a deficient number, since it is larger than the sum of its proper divisors (12253872247695).

21220120211121 is a wasteful number, since it uses less digits than its factorization.

21220120211121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2554486693 (or 2554486690 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21220120211121 its reverse (12111202102212), we get a palindrome (33331322313333).

The spelling of 21220120211121 in words is "twenty-one trillion, two hundred twenty billion, one hundred twenty million, two hundred eleven thousand, one hundred twenty-one".