21100321310221 has 2 divisors, whose sum is σ = 21100321310222. Its totient is φ = 21100321310220.

The previous prime is 21100321310171. The next prime is 21100321310239. The reversal of 21100321310221 is 12201312300112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19342008182025 + 1758313128196 = 4397955^2 + 1326014^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21100321310221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21100321310521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550160655110 + 10550160655111.

It is an arithmetic number, because the mean of its divisors is an integer number (10550160655111).

Almost surely, 2^{21100321310221} is an apocalyptic number.

It is an amenable number.

21100321310221 is a deficient number, since it is larger than the sum of its proper divisors (1).

21100321310221 is an equidigital number, since it uses as much as digits as its factorization.

21100321310221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 21100321310221 its reverse (12201312300112), we get a palindrome (33301633610333).

The spelling of 21100321310221 in words is "twenty-one trillion, one hundred billion, three hundred twenty-one million, three hundred ten thousand, two hundred twenty-one".