212100222221 has 8 divisors (see below), whose sum is σ = 214348125624. Its totient is φ = 209858826240.

The previous prime is 212100222209. The next prime is 212100222227. The reversal of 212100222221 is 122222001212.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 24620748100 + 187479474121 = 156910^2 + 432989^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 212100222221 - 2¹⁰ = 212100221197 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 212100222221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212100222227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1561310 + ... + 1691711.

It is an arithmetic number, because the mean of its divisors is an integer number (26793515703).

Almost surely, 2^212100222221 is an apocalyptic number.

It is an amenable number.

212100222221 is a deficient number, since it is larger than the sum of its proper divisors (2247903403).

212100222221 is a wasteful number, since it uses less digits than its factorization.

212100222221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3253711.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 212100222221 its reverse (122222001212), we get a palindrome (334322223433).

The spelling of 212100222221 in words is "two hundred twelve billion, one hundred million, two hundred twenty-two thousand, two hundred twenty-one".