20213221133221 has 4 divisors (see below), whose sum is σ = 20213652911200. Its totient is φ = 20212789355244.

The previous prime is 20213221133219. The next prime is 20213221133233. The reversal of 20213221133221 is 12233112231202.

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 20213221133221 - 2¹ = 20213221133219 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 (20213221133291) 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, 215818761 + ... + 215912398.

It is an arithmetic number, because the mean of its divisors is an integer number (5053413227800).

Almost surely, 2^{20213221133221} is an apocalyptic number.

It is an amenable number.

20213221133221 is a deficient number, since it is larger than the sum of its proper divisors (431777979).

20213221133221 is an equidigital number, since it uses as much as digits as its factorization.

20213221133221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 431777978.

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

Adding to 20213221133221 its reverse (12233112231202), we get a palindrome (32446333364423).

The spelling of 20213221133221 in words is "twenty trillion, two hundred thirteen billion, two hundred twenty-one million, one hundred thirty-three thousand, two hundred twenty-one".