2100012221221 has 2 divisors, whose sum is σ = 2100012221222. Its totient is φ = 2100012221220.

The previous prime is 2100012221213. The next prime is 2100012221243. The reversal of 2100012221221 is 1221222100012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1446032705121 + 653979516100 = 1202511^2 + 808690^2 .

It is a cyclic number.

It is not a de Polignac number, because 2100012221221 - 2³ = 2100012221213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2100012221195 and 2100012221204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2100012221621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1050006110610 + 1050006110611.

It is an arithmetic number, because the mean of its divisors is an integer number (1050006110611).

Almost surely, 2^{2100012221221} is an apocalyptic number.

It is an amenable number.

2100012221221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2100012221221 is an equidigital number, since it uses as much as digits as its factorization.

2100012221221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 2100012221221 its reverse (1221222100012), we get a palindrome (3321234321233).

The spelling of 2100012221221 in words is "two trillion, one hundred billion, twelve million, two hundred twenty-one thousand, two hundred twenty-one".