210021212102221 has 8 divisors (see below), whose sum is σ = 226180981739160. Its totient is φ = 193862055577152.

The previous prime is 210021212102203. The next prime is 210021212102297. The reversal of 210021212102221 is 122201212120012.

It can be written as a sum of positive squares in 4 ways, for example, as 1933807296996 + 208087404805225 = 1390614^2 + 14425235^2 .

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 210021212102221 - 2²⁹ = 210020675231309 is a prime.

It is a super-2 number, since 2×210021212102221² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210021212102921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 152566390 + ... + 153936823.

It is an arithmetic number, because the mean of its divisors is an integer number (28272622717395).

Almost surely, 2^{210021212102221} is an apocalyptic number.

It is an amenable number.

210021212102221 is a deficient number, since it is larger than the sum of its proper divisors (16159769636939).

210021212102221 is a wasteful number, since it uses less digits than its factorization.

210021212102221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306555935.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 210021212102221 its reverse (122201212120012), we get a palindrome (332222424222233).

The spelling of 210021212102221 in words is "two hundred ten trillion, twenty-one billion, two hundred twelve million, one hundred two thousand, two hundred twenty-one".