212202211221 has 192 divisors, whose sum is σ = 438325655040. Its totient is φ = 95204229120.

The previous prime is 212202211217. The next prime is 212202211307. The reversal of 212202211221 is 122112202212.

It is a happy number.

212202211221 is a `hidden beast` number, since 2 + 1 + 220 + 221 + 1 + 221 = 666.

212202211221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 212202211221 - 2² = 212202211217 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 212202211194 and 212202211203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212202211021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 26491465 + ... + 26499473.

It is an arithmetic number, because the mean of its divisors is an integer number (2282946120).

Almost surely, 2^212202211221 is an apocalyptic number.

212202211221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

212202211221 is an abundant number, since it is smaller than the sum of its proper divisors (226123443819).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

212202211221 is a wasteful number, since it uses less digits than its factorization.

212202211221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8236 (or 8233 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 212202211221 its reverse (122112202212), we get a palindrome (334314413433).

Subtracting from 212202211221 its reverse (122112202212), we obtain a palindrome (90090009009).

The spelling of 212202211221 in words is "two hundred twelve billion, two hundred two million, two hundred eleven thousand, two hundred twenty-one".