212201022221 has 4 divisors (see below), whose sum is σ = 214147820700. Its totient is φ = 210254223744.

The previous prime is 212201022203. The next prime is 212201022301. The reversal of 212201022221 is 122220102212.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 189215430121 + 22985592100 = 434989^2 + 151610^2 .

It is a cyclic number.

It is not a de Polignac number, because 212201022221 - 2¹⁴ = 212201005837 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 212201022221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212201025221) 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, 973399076 + ... + 973399293.

It is an arithmetic number, because the mean of its divisors is an integer number (53536955175).

Almost surely, 2^212201022221 is an apocalyptic number.

It is an amenable number.

212201022221 is a deficient number, since it is larger than the sum of its proper divisors (1946798479).

212201022221 is a wasteful number, since it uses less digits than its factorization.

212201022221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1946798478.

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

Adding to 212201022221 its reverse (122220102212), we get a palindrome (334421124433).

The spelling of 212201022221 in words is "two hundred twelve billion, two hundred one million, twenty-two thousand, two hundred twenty-one".