12210021001221 has 4 divisors (see below), whose sum is σ = 16280028001632. Its totient is φ = 8140014000812.

The previous prime is 12210021001181. The next prime is 12210021001223. The reversal of 12210021001221 is 12210012001221.

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 12210021001221 - 2¹⁷ = 12210020870149 is a prime.

It is a super-2 number, since 2×12210021001221² (a number of 27 digits) contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 12210021001221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12210021001223) 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, 2035003500201 + ... + 2035003500206.

It is an arithmetic number, because the mean of its divisors is an integer number (4070007000408).

Almost surely, 2^{12210021001221} is an apocalyptic number.

It is an amenable number.

12210021001221 is a deficient number, since it is larger than the sum of its proper divisors (4070007000411).

12210021001221 is an equidigital number, since it uses as much as digits as its factorization.

12210021001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4070007000410.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 12210021001221 its reverse (12210012001221), we get a palindrome (24420033002442).

Subtracting from 12210021001221 its reverse (12210012001221), we obtain a square (9000000 = 3000²).

The spelling of 12210021001221 in words is "twelve trillion, two hundred ten billion, twenty-one million, one thousand, two hundred twenty-one".