211200102100021 has 2 divisors, whose sum is σ = 211200102100022. Its totient is φ = 211200102100020.

The previous prime is 211200102100007. The next prime is 211200102100109. The reversal of 211200102100021 is 120001201002112.

211200102100021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 178683078483121 + 32517023616900 = 13367239^2 + 5702370^2 .

It is a cyclic number.

It is not a de Polignac number, because 211200102100021 - 2⁷ = 211200102099893 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 211200102099974 and 211200102100010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211200102100121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105600051050010 + 105600051050011.

It is an arithmetic number, because the mean of its divisors is an integer number (105600051050011).

Almost surely, 2^{211200102100021} is an apocalyptic number.

It is an amenable number.

211200102100021 is a deficient number, since it is larger than the sum of its proper divisors (1).

211200102100021 is an equidigital number, since it uses as much as digits as its factorization.

211200102100021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 211200102100021 its reverse (120001201002112), we get a palindrome (331201303102133).

The spelling of 211200102100021 in words is "two hundred eleven trillion, two hundred billion, one hundred two million, one hundred thousand, twenty-one".