20210200100021 has 2 divisors, whose sum is σ = 20210200100022. Its totient is φ = 20210200100020.

The previous prime is 20210200099997. The next prime is 20210200100023. The reversal of 20210200100021 is 12000100201202.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13961350047121 + 6248850052900 = 3736489^2 + 2499770^2 .

It is a cyclic number.

It is not a de Polignac number, because 20210200100021 - 2³⁸ = 19935322193077 is a prime.

Together with 20210200100023, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20210200099975 and 20210200100011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20210200100023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10105100050010 + 10105100050011.

It is an arithmetic number, because the mean of its divisors is an integer number (10105100050011).

Almost surely, 2^{20210200100021} is an apocalyptic number.

It is an amenable number.

20210200100021 is a deficient number, since it is larger than the sum of its proper divisors (1).

20210200100021 is an equidigital number, since it uses as much as digits as its factorization.

20210200100021 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 11.

Adding to 20210200100021 its reverse (12000100201202), we get a palindrome (32210300301223).

The spelling of 20210200100021 in words is "twenty trillion, two hundred ten billion, two hundred million, one hundred thousand, twenty-one".