212222122121 has 4 divisors (see below), whose sum is σ = 212233292544. Its totient is φ = 212210951700.

The previous prime is 212222122103. The next prime is 212222122129. The reversal of 212222122121 is 121221222212.

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 a de Polignac number, because none of the positive numbers 2^k-212222122121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212222122093 and 212222122102.

It is not an unprimeable number, because it can be changed into a prime (212222122129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5556665 + ... + 5594726.

It is an arithmetic number, because the mean of its divisors is an integer number (53058323136).

Almost surely, 2^212222122121 is an apocalyptic number.

It is an amenable number.

212222122121 is a deficient number, since it is larger than the sum of its proper divisors (11170423).

212222122121 is a wasteful number, since it uses less digits than its factorization.

212222122121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11170422.

The product of its digits is 256, while the sum is 20.

Adding to 212222122121 its reverse (121221222212), we get a palindrome (333443344333).

The spelling of 212222122121 in words is "two hundred twelve billion, two hundred twenty-two million, one hundred twenty-two thousand, one hundred twenty-one".