212212112221 has 4 divisors (see below), whose sum is σ = 212263888000. Its totient is φ = 212160336444.

The previous prime is 212212112209. The next prime is 212212112261. The reversal of 212212112221 is 122211212212.

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 212212112221 - 2¹⁹ = 212211587933 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212212112261) 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, 25881741 + ... + 25889938.

It is an arithmetic number, because the mean of its divisors is an integer number (53065972000).

Almost surely, 2^212212112221 is an apocalyptic number.

It is an amenable number.

212212112221 is a deficient number, since it is larger than the sum of its proper divisors (51775779).

212212112221 is an equidigital number, since it uses as much as digits as its factorization.

212212112221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51775778.

The product of its digits is 128, while the sum is 19.

Adding to 212212112221 its reverse (122211212212), we get a palindrome (334423324433).

Subtracting from 212212112221 its reverse (122211212212), we obtain a palindrome (90000900009).

The spelling of 212212112221 in words is "two hundred twelve billion, two hundred twelve million, one hundred twelve thousand, two hundred twenty-one".