2111100020021 has 2 divisors, whose sum is σ = 2111100020022. Its totient is φ = 2111100020020.

The previous prime is 2111100020017. The next prime is 2111100020033. The reversal of 2111100020021 is 1200200011112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1717381419121 + 393718600900 = 1310489^2 + 627470^2 .

It is a cyclic number.

It is not a de Polignac number, because 2111100020021 - 2² = 2111100020017 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2111100019984 and 2111100020011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2111100020621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1055550010010 + 1055550010011.

It is an arithmetic number, because the mean of its divisors is an integer number (1055550010011).

Almost surely, 2^{2111100020021} is an apocalyptic number.

It is an amenable number.

2111100020021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2111100020021 is an equidigital number, since it uses as much as digits as its factorization.

2111100020021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 2111100020021 its reverse (1200200011112), we get a palindrome (3311300031133).

The spelling of 2111100020021 in words is "two trillion, one hundred eleven billion, one hundred million, twenty thousand, twenty-one".