2121002211221 has 4 divisors (see below), whose sum is σ = 2121026648832. Its totient is φ = 2120977773612.

The previous prime is 2121002211173. The next prime is 2121002211253. The reversal of 2121002211221 is 1221122001212.

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 2121002211221 - 2⁶ = 2121002211157 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 2121002211221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121002219221) 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, 12088151 + ... + 12262356.

It is an arithmetic number, because the mean of its divisors is an integer number (530256662208).

Almost surely, 2^{2121002211221} is an apocalyptic number.

It is an amenable number.

2121002211221 is a deficient number, since it is larger than the sum of its proper divisors (24437611).

2121002211221 is an equidigital number, since it uses as much as digits as its factorization.

2121002211221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24437610.

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

Adding to 2121002211221 its reverse (1221122001212), we get a palindrome (3342124212433).

The spelling of 2121002211221 in words is "two trillion, one hundred twenty-one billion, two million, two hundred eleven thousand, two hundred twenty-one".