21222011210221 has 4 divisors (see below), whose sum is σ = 21222487223392. Its totient is φ = 21221535197052.

The previous prime is 21222011210219. The next prime is 21222011210237. The reversal of 21222011210221 is 12201211022212.

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 21222011210221 - 2¹ = 21222011210219 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 (21222011210291) 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, 237939705 + ... + 238028878.

It is an arithmetic number, because the mean of its divisors is an integer number (5305621805848).

Almost surely, 2^{21222011210221} is an apocalyptic number.

It is an amenable number.

21222011210221 is a deficient number, since it is larger than the sum of its proper divisors (476013171).

21222011210221 is an equidigital number, since it uses as much as digits as its factorization.

21222011210221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 476013170.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21222011210221 its reverse (12201211022212), we get a palindrome (33423222232433).

The spelling of 21222011210221 in words is "twenty-one trillion, two hundred twenty-two billion, eleven million, two hundred ten thousand, two hundred twenty-one".