212112112221 has 6 divisors (see below), whose sum is σ = 306384162110. Its totient is φ = 141408074808.

The previous prime is 212112112213. The next prime is 212112112297. The reversal of 212112112221 is 122211211212.

212112112221 is a `hidden beast` number, since 21 + 211 + 211 + 2 + 221 = 666.

It can be written as a sum of positive squares in only one way, i.e., 192620043225 + 19492068996 = 438885^2 + 139614^2 .

It is not a de Polignac number, because 212112112221 - 2³ = 212112112213 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 212112112194 and 212112112203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212112112721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11784006226 + ... + 11784006243.

Almost surely, 2^212112112221 is an apocalyptic number.

It is an amenable number.

212112112221 is a deficient number, since it is larger than the sum of its proper divisors (94272049889).

212112112221 is a wasteful number, since it uses less digits than its factorization.

212112112221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23568012475 (or 23568012472 counting only the distinct ones).

The product of its digits is 64, while the sum is 18.

Adding to 212112112221 its reverse (122211211212), we get a palindrome (334323323433).

The spelling of 212112112221 in words is "two hundred twelve billion, one hundred twelve million, one hundred twelve thousand, two hundred twenty-one".