21221220220211 has 24 divisors (see below), whose sum is σ = 23497171605600. Its totient is φ = 19150733733120.

The previous prime is 21221220220183. The next prime is 21221220220217. The reversal of 21221220220211 is 11202202212212.

It is not a de Polignac number, because 21221220220211 - 2³⁴ = 21204040351027 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21221220220217) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9408521 + ... + 11443893.

It is an arithmetic number, because the mean of its divisors is an integer number (979048816900).

Almost surely, 2^{21221220220211} is an apocalyptic number.

21221220220211 is a deficient number, since it is larger than the sum of its proper divisors (2275951385389).

21221220220211 is a wasteful number, since it uses less digits than its factorization.

21221220220211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2036027 (or 2036016 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 21221220220211 its reverse (11202202212212), we get a palindrome (32423422432423).

The spelling of 21221220220211 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred twenty million, two hundred twenty thousand, two hundred eleven".