21221211030221 has 4 divisors (see below), whose sum is σ = 21227068392672. Its totient is φ = 21215353667772.

The previous prime is 21221211030163. The next prime is 21221211030233. The reversal of 21221211030221 is 12203011212212.

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 21221211030221 - 2⁶ = 21221211030157 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21221211030193 and 21221211030202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221211030251) 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, 2928675791 + ... + 2928683036.

It is an arithmetic number, because the mean of its divisors is an integer number (5306767098168).

Almost surely, 2^{21221211030221} is an apocalyptic number.

It is an amenable number.

21221211030221 is a deficient number, since it is larger than the sum of its proper divisors (5857362451).

21221211030221 is an equidigital number, since it uses as much as digits as its factorization.

21221211030221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5857362450.

The product of its (nonzero) digits is 192, while the sum is 20.

Adding to 21221211030221 its reverse (12203011212212), we get a palindrome (33424222242433).

The spelling of 21221211030221 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred eleven million, thirty thousand, two hundred twenty-one".