21222110202221 has 4 divisors (see below), whose sum is σ = 21222985473312. Its totient is φ = 21221234931132.

The previous prime is 21222110202211. The next prime is 21222110202233. The reversal of 21222110202221 is 12220201122212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21222110202221 - 2¹⁰ = 21222110201197 is a prime.

It is a super-2 number, since 2×21222110202221² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21222110202193 and 21222110202202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222110202211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 437599175 + ... + 437647668.

It is an arithmetic number, because the mean of its divisors is an integer number (5305746368328).

Almost surely, 2^{21222110202221} is an apocalyptic number.

It is an amenable number.

21222110202221 is a deficient number, since it is larger than the sum of its proper divisors (875271091).

21222110202221 is an equidigital number, since it uses as much as digits as its factorization.

21222110202221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 875271090.

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

Adding to 21222110202221 its reverse (12220201122212), we get a palindrome (33442311324433).

The spelling of 21222110202221 in words is "twenty-one trillion, two hundred twenty-two billion, one hundred ten million, two hundred two thousand, two hundred twenty-one".