21223210133221 has 4 divisors (see below), whose sum is σ = 21250808586700. Its totient is φ = 21195611679744.

The previous prime is 21223210133131. The next prime is 21223210133239. The reversal of 21223210133221 is 12233101232212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15761781352321 + 5461428780900 = 3970111^2 + 2336970^2 .

It is a cyclic number.

It is not a de Polignac number, because 21223210133221 - 2¹¹ = 21223210131173 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21223210133621) 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, 13799225586 + ... + 13799227123.

It is an arithmetic number, because the mean of its divisors is an integer number (5312702146675).

Almost surely, 2^{21223210133221} is an apocalyptic number.

It is an amenable number.

21223210133221 is a deficient number, since it is larger than the sum of its proper divisors (27598453479).

21223210133221 is an equidigital number, since it uses as much as digits as its factorization.

21223210133221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27598453478.

The product of its (nonzero) digits is 1728, while the sum is 25.

Adding to 21223210133221 its reverse (12233101232212), we get a palindrome (33456311365433).

The spelling of 21223210133221 in words is "twenty-one trillion, two hundred twenty-three billion, two hundred ten million, one hundred thirty-three thousand, two hundred twenty-one".