10001221212221 has 8 divisors (see below), whose sum is σ = 10005998580864. Its totient is φ = 9996444795520.

The previous prime is 10001221212163. The next prime is 10001221212247. The reversal of 10001221212221 is 12221212210001.

10001221212221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 10001221212221 - 2²⁶ = 10001154103357 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 10001221212221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10001221212251) 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, 21239981 + ... + 21705741.

It is an arithmetic number, because the mean of its divisors is an integer number (1250749822608).

Almost surely, 2^{10001221212221} is an apocalyptic number.

It is an amenable number.

10001221212221 is a deficient number, since it is larger than the sum of its proper divisors (4777368643).

10001221212221 is an equidigital number, since it uses as much as digits as its factorization.

10001221212221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 475971.

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

Adding to 10001221212221 its reverse (12221212210001), we get a palindrome (22222433422222).

The spelling of 10001221212221 in words is "ten trillion, one billion, two hundred twenty-one million, two hundred twelve thousand, two hundred twenty-one".