2100212221221 has 28 divisors (see below), whose sum is σ = 3195876108352. Its totient is φ = 1379243814696.

The previous prime is 2100212221193. The next prime is 2100212221241. The reversal of 2100212221221 is 1221222120012.

It is a happy number.

2100212221221 is a `hidden beast` number, since 2 + 10 + 0 + 212 + 221 + 221 = 666.

It is not a de Polignac number, because 2100212221221 - 2⁵ = 2100212221189 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2100212221194 and 2100212221203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2100212221241) 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 27 ways as a sum of consecutive naturals, for example, 21450781 + ... + 21548466.

Almost surely, 2^{2100212221221} is an apocalyptic number.

It is an amenable number.

2100212221221 is a deficient number, since it is larger than the sum of its proper divisors (1095663887131).

2100212221221 is an frugal number, since it uses more digits than its factorization.

2100212221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42999332 (or 42999317 counting only the distinct ones).

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

Adding to 2100212221221 its reverse (1221222120012), we get a palindrome (3321434341233).

The spelling of 2100212221221 in words is "two trillion, one hundred billion, two hundred twelve million, two hundred twenty-one thousand, two hundred twenty-one".