21022100212221 has 48 divisors (see below), whose sum is σ = 32707986625600. Its totient is φ = 12967860519936.

The previous prime is 21022100212207. The next prime is 21022100212229. The reversal of 21022100212221 is 12221200122012.

It is a happy number.

21022100212221 is a `hidden beast` number, since 2 + 10 + 221 + 0 + 0 + 212 + 221 = 666.

It is not a de Polignac number, because 21022100212221 - 2⁷ = 21022100212093 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21022100212194 and 21022100212203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21022100212229) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 382129965 + ... + 382184973.

Almost surely, 2^{21022100212221} is an apocalyptic number.

It is an amenable number.

21022100212221 is a deficient number, since it is larger than the sum of its proper divisors (11685886413379).

21022100212221 is a wasteful number, since it uses less digits than its factorization.

21022100212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107050 (or 107047 counting only the distinct ones).

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

Adding to 21022100212221 its reverse (12221200122012), we get a palindrome (33243300334233).

The spelling of 21022100212221 in words is "twenty-one trillion, twenty-two billion, one hundred million, two hundred twelve thousand, two hundred twenty-one".