21023211112021 has 2 divisors, whose sum is σ = 21023211112022. Its totient is φ = 21023211112020.

The previous prime is 21023211112019. The next prime is 21023211112109. The reversal of 21023211112021 is 12021111232012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20951574589521 + 71636522500 = 4577289^2 + 267650^2 .

It is a cyclic number.

It is not a de Polignac number, because 21023211112021 - 2¹ = 21023211112019 is a prime.

Together with 21023211112019, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21023211112021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21023211112721) 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, 10511605556010 + 10511605556011.

It is an arithmetic number, because the mean of its divisors is an integer number (10511605556011).

Almost surely, 2^{21023211112021} is an apocalyptic number.

It is an amenable number.

21023211112021 is a deficient number, since it is larger than the sum of its proper divisors (1).

21023211112021 is an equidigital number, since it uses as much as digits as its factorization.

21023211112021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 21023211112021 its reverse (12021111232012), we get a palindrome (33044322344033).

The spelling of 21023211112021 in words is "twenty-one trillion, twenty-three billion, two hundred eleven million, one hundred twelve thousand, twenty-one".