2101211210221 has 2 divisors, whose sum is σ = 2101211210222. Its totient is φ = 2101211210220.

The previous prime is 2101211210173. The next prime is 2101211210233. The reversal of 2101211210221 is 1220121121012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1637094660100 + 464116550121 = 1279490^2 + 681261^2 .

It is a cyclic number.

It is not a de Polignac number, because 2101211210221 - 2⁹ = 2101211209709 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2101211210195 and 2101211210204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2101211210621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1050605605110 + 1050605605111.

It is an arithmetic number, because the mean of its divisors is an integer number (1050605605111).

Almost surely, 2^{2101211210221} is an apocalyptic number.

It is an amenable number.

2101211210221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2101211210221 is an equidigital number, since it uses as much as digits as its factorization.

2101211210221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 2101211210221 its reverse (1220121121012), we get a palindrome (3321332331233).

The spelling of 2101211210221 in words is "two trillion, one hundred one billion, two hundred eleven million, two hundred ten thousand, two hundred twenty-one".