200020012109821 has 2 divisors, whose sum is σ = 200020012109822. Its totient is φ = 200020012109820.

The previous prime is 200020012109779. The next prime is 200020012109969. The reversal of 200020012109821 is 128901210020002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 137915194312900 + 62104817796921 = 11743730^2 + 7880661^2 .

It is a cyclic number.

It is not a de Polignac number, because 200020012109821 - 2⁷ = 200020012109693 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 200020012109821.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (200020012109321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100010006054910 + 100010006054911.

It is an arithmetic number, because the mean of its divisors is an integer number (100010006054911).

Almost surely, 2^{200020012109821} is an apocalyptic number.

It is an amenable number.

200020012109821 is a deficient number, since it is larger than the sum of its proper divisors (1).

200020012109821 is an equidigital number, since it uses as much as digits as its factorization.

200020012109821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 28.

Adding to 200020012109821 its reverse (128901210020002), we get a palindrome (328921222129823).

The spelling of 200020012109821 in words is "two hundred trillion, twenty billion, twelve million, one hundred nine thousand, eight hundred twenty-one".