202000210100021 has 2 divisors, whose sum is σ = 202000210100022. Its totient is φ = 202000210100020.

The previous prime is 202000210099981. The next prime is 202000210100023. The reversal of 202000210100021 is 120001012000202.

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., 201982052537521 + 18157562500 = 14212039^2 + 134750^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-202000210100021 is a prime.

Together with 202000210100023, 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 = 202000210099975 and 202000210100011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (202000210100023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101000105050010 + 101000105050011.

It is an arithmetic number, because the mean of its divisors is an integer number (101000105050011).

Almost surely, 2^{202000210100021} is an apocalyptic number.

It is an amenable number.

202000210100021 is a deficient number, since it is larger than the sum of its proper divisors (1).

202000210100021 is an equidigital number, since it uses as much as digits as its factorization.

202000210100021 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 11.

Adding to 202000210100021 its reverse (120001012000202), we get a palindrome (322001222100223).

The spelling of 202000210100021 in words is "two hundred two trillion, two hundred ten million, one hundred thousand, twenty-one".