222121210221 has 6 divisors (see below), whose sum is σ = 320841748110. Its totient is φ = 148080806808.

The previous prime is 222121210217. The next prime is 222121210253. The reversal of 222121210221 is 122012121222.

It is a happy number.

222121210221 is a `hidden beast` number, since 2 + 221 + 212 + 10 + 221 = 666.

It can be written as a sum of positive squares in only one way, i.e., 145218155625 + 76903054596 = 381075^2 + 277314^2 .

It is not a de Polignac number, because 222121210221 - 2² = 222121210217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 222121210194 and 222121210203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222121210121) 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, 12340067226 + ... + 12340067243.

It is an arithmetic number, because the mean of its divisors is an integer number (53473624685).

Almost surely, 2^222121210221 is an apocalyptic number.

It is an amenable number.

222121210221 is a deficient number, since it is larger than the sum of its proper divisors (98720537889).

222121210221 is a wasteful number, since it uses less digits than its factorization.

222121210221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24680134475 (or 24680134472 counting only the distinct ones).

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

Adding to 222121210221 its reverse (122012121222), we get a palindrome (344133331443).

The spelling of 222121210221 in words is "two hundred twenty-two billion, one hundred twenty-one million, two hundred ten thousand, two hundred twenty-one".