200021101997 has 2 divisors, whose sum is σ = 200021101998. Its totient is φ = 200021101996.

The previous prime is 200021101979. The next prime is 200021102023. The reversal of 200021101997 is 799101120002.

Together with previous prime (200021101979) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 180783134596 + 19237967401 = 425186^2 + 138701^2 .

It is a cyclic number.

It is not a de Polignac number, because 200021101997 - 2⁸ = 200021101741 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (200021101967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100010550998 + 100010550999.

It is an arithmetic number, because the mean of its divisors is an integer number (100010550999).

Almost surely, 2^200021101997 is an apocalyptic number.

It is an amenable number.

200021101997 is a deficient number, since it is larger than the sum of its proper divisors (1).

200021101997 is an equidigital number, since it uses as much as digits as its factorization.

200021101997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2268, while the sum is 32.

Adding to 200021101997 its reverse (799101120002), we get a palindrome (999122221999).

The spelling of 200021101997 in words is "two hundred billion, twenty-one million, one hundred one thousand, nine hundred ninety-seven".