21220112010221 has 8 divisors (see below), whose sum is σ = 21423046001400. Its totient is φ = 21017984914432.

The previous prime is 21220112010211. The next prime is 21220112010233. The reversal of 21220112010221 is 12201021102212.

It can be written as a sum of positive squares in 4 ways, for example, as 529895187721 + 20690216822500 = 727939^2 + 4548650^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21220112010221 - 2²⁶ = 21220044901357 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21220112010221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220112010211) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 201671000 + ... + 201776193.

It is an arithmetic number, because the mean of its divisors is an integer number (2677880750175).

Almost surely, 2^{21220112010221} is an apocalyptic number.

It is an amenable number.

21220112010221 is a deficient number, since it is larger than the sum of its proper divisors (202933991179).

21220112010221 is a wasteful number, since it uses less digits than its factorization.

21220112010221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 403447695.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21220112010221 its reverse (12201021102212), we get a palindrome (33421133112433).

The spelling of 21220112010221 in words is "twenty-one trillion, two hundred twenty billion, one hundred twelve million, ten thousand, two hundred twenty-one".