21012222102221 has 8 divisors (see below), whose sum is σ = 24504049099200. Its totient is φ = 18010476087324.

The previous prime is 21012222102211. The next prime is 21012222102239. The reversal of 21012222102221 is 12220122221012.

It is not a de Polignac number, because 21012222102221 - 2³⁸ = 20737344195277 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21012222102193 and 21012222102202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012222102211) 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, 30630061031 + ... + 30630061716.

It is an arithmetic number, because the mean of its divisors is an integer number (3063006137400).

Almost surely, 2^{21012222102221} is an apocalyptic number.

It is an amenable number.

21012222102221 is a deficient number, since it is larger than the sum of its proper divisors (3491826996979).

21012222102221 is an frugal number, since it uses more digits than its factorization.

21012222102221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61260122768 (or 61260122754 counting only the distinct ones).

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

Adding to 21012222102221 its reverse (12220122221012), we get a palindrome (33232344323233).

The spelling of 21012222102221 in words is "twenty-one trillion, twelve billion, two hundred twenty-two million, one hundred two thousand, two hundred twenty-one".