2121211212121 has 16 divisors (see below), whose sum is σ = 2133136152576. Its totient is φ = 2109326769936.

The previous prime is 2121211212089. The next prime is 2121211212161. The reversal of 2121211212121 is 1212121121212.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 2121211212121 - 2⁵ = 2121211212089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2121211212161) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 278846100 + ... + 278853706.

It is an arithmetic number, because the mean of its divisors is an integer number (133321009536).

Almost surely, 2^{2121211212121} is an apocalyptic number.

It is an amenable number.

2121211212121 is a deficient number, since it is larger than the sum of its proper divisors (11924940455).

2121211212121 is a wasteful number, since it uses less digits than its factorization.

2121211212121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10068.

The product of its digits is 64, while the sum is 19.

Adding to 2121211212121 its reverse (1212121121212), we get a palindrome (3333332333333).

Subtracting from 2121211212121 its reverse (1212121121212), we obtain a palindrome (909090090909).

It can be divided in two parts, 2121211 and 212121, that added together give a palindrome (2333332).

The spelling of 2121211212121 in words is "two trillion, one hundred twenty-one billion, two hundred eleven million, two hundred twelve thousand, one hundred twenty-one".