21220110111221 has 8 divisors (see below), whose sum is σ = 24649120879104. Its totient is φ = 17890490959920.

The previous prime is 21220110111197. The next prime is 21220110111223. The reversal of 21220110111221 is 12211101102212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21220110111221 - 2⁶ = 21220110111157 is a prime.

It is a super-2 number, since 2×21220110111221² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21220110111221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220110111223) 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 7 ways as a sum of consecutive naturals, for example, 24847903685 + ... + 24847904538.

It is an arithmetic number, because the mean of its divisors is an integer number (3081140109888).

Almost surely, 2^{21220110111221} is an apocalyptic number.

It is an amenable number.

21220110111221 is a deficient number, since it is larger than the sum of its proper divisors (3429010767883).

21220110111221 is an equidigital number, since it uses as much as digits as its factorization.

21220110111221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49695808291.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21220110111221 its reverse (12211101102212), we get a palindrome (33431211213433).

Subtracting from 21220110111221 its reverse (12211101102212), we obtain a palindrome (9009009009009).

The spelling of 21220110111221 in words is "twenty-one trillion, two hundred twenty billion, one hundred ten million, one hundred eleven thousand, two hundred twenty-one".