21304211110421 has 2 divisors, whose sum is σ = 21304211110422. Its totient is φ = 21304211110420.

The previous prime is 21304211110409. The next prime is 21304211110423. The reversal of 21304211110421 is 12401111240312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14372522614321 + 6931688496100 = 3791111^2 + 2632810^2 .

It is a cyclic number.

It is not a de Polignac number, because 21304211110421 - 2³⁴ = 21287031241237 is a prime.

It is a super-2 number, since 2×21304211110421² (a number of 27 digits) contains 22 as substring.

Together with 21304211110423, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21304211110423) 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, 10652105555210 + 10652105555211.

It is an arithmetic number, because the mean of its divisors is an integer number (10652105555211).

Almost surely, 2^{21304211110421} is an apocalyptic number.

It is an amenable number.

21304211110421 is a deficient number, since it is larger than the sum of its proper divisors (1).

21304211110421 is an equidigital number, since it uses as much as digits as its factorization.

21304211110421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 384, while the sum is 23.

Adding to 21304211110421 its reverse (12401111240312), we get a palindrome (33705322350733).

The spelling of 21304211110421 in words is "twenty-one trillion, three hundred four billion, two hundred eleven million, one hundred ten thousand, four hundred twenty-one".