21201102022221 has 32 divisors (see below), whose sum is σ = 34266368010240. Its totient is φ = 12848417478000.

The previous prime is 21201102022211. The next prime is 21201102022223. The reversal of 21201102022221 is 12222020110212.

It is a happy number.

It is not a de Polignac number, because 21201102022221 - 2³⁰ = 21200028280397 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21201102022194 and 21201102022203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201102022223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3179026 + ... + 7246268.

It is an arithmetic number, because the mean of its divisors is an integer number (1070824000320).

Almost surely, 2^{21201102022221} is an apocalyptic number.

It is an amenable number.

21201102022221 is a deficient number, since it is larger than the sum of its proper divisors (13065265988019).

21201102022221 is a wasteful number, since it uses less digits than its factorization.

21201102022221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4084814 (or 4084808 counting only the distinct ones).

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

Adding to 21201102022221 its reverse (12222020110212), we get a palindrome (33423122132433).

The spelling of 21201102022221 in words is "twenty-one trillion, two hundred one billion, one hundred two million, twenty-two thousand, two hundred twenty-one".