2101000121221 has 2 divisors, whose sum is σ = 2101000121222. Its totient is φ = 2101000121220.

The previous prime is 2101000121219. The next prime is 2101000121239. The reversal of 2101000121221 is 1221210001012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1979328216996 + 121671904225 = 1406886^2 + 348815^2 .

It is a cyclic number.

It is not a de Polignac number, because 2101000121221 - 2¹ = 2101000121219 is a prime.

Together with 2101000121219, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2101000121201) 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 as a sum of consecutive naturals, namely, 1050500060610 + 1050500060611.

It is an arithmetic number, because the mean of its divisors is an integer number (1050500060611).

Almost surely, 2^{2101000121221} is an apocalyptic number.

It is an amenable number.

2101000121221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2101000121221 is an equidigital number, since it uses as much as digits as its factorization.

2101000121221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 2101000121221 its reverse (1221210001012), we get a palindrome (3322210122233).

The spelling of 2101000121221 in words is "two trillion, one hundred one billion, one hundred twenty-one thousand, two hundred twenty-one".