21110012002021 has 2 divisors, whose sum is σ = 21110012002022. Its totient is φ = 21110012002020.

The previous prime is 21110012001979. The next prime is 21110012002061. The reversal of 21110012002021 is 12020021001112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16666896065121 + 4443115936900 = 4082511^2 + 2107870^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21110012002021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21110012001992 and 21110012002010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21110012002061) 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, 10555006001010 + 10555006001011.

It is an arithmetic number, because the mean of its divisors is an integer number (10555006001011).

Almost surely, 2^{21110012002021} is an apocalyptic number.

It is an amenable number.

21110012002021 is a deficient number, since it is larger than the sum of its proper divisors (1).

21110012002021 is an equidigital number, since it uses as much as digits as its factorization.

21110012002021 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 21110012002021 its reverse (12020021001112), we get a palindrome (33130033003133).

The spelling of 21110012002021 in words is "twenty-one trillion, one hundred ten billion, twelve million, two thousand, twenty-one".