10001021200021 has 2 divisors, whose sum is σ = 10001021200022. Its totient is φ = 10001021200020.

The previous prime is 10001021200013. The next prime is 10001021200033. The reversal of 10001021200021 is 12000212010001.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9083659515921 + 917361684100 = 3013911^2 + 957790^2 .

It is a cyclic number.

It is not a de Polignac number, because 10001021200021 - 2³ = 10001021200013 is a prime.

It is a super-3 number, since 3×10001021200021³ (a number of 40 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 10001021199980 and 10001021200007.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10001021200061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5000510600010 + 5000510600011.

It is an arithmetic number, because the mean of its divisors is an integer number (5000510600011).

Almost surely, 2^{10001021200021} is an apocalyptic number.

It is an amenable number.

10001021200021 is a deficient number, since it is larger than the sum of its proper divisors (1).

10001021200021 is an equidigital number, since it uses as much as digits as its factorization.

10001021200021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 10001021200021 its reverse (12000212010001), we get a palindrome (22001233210022).

The spelling of 10001021200021 in words is "ten trillion, one billion, twenty-one million, two hundred thousand, twenty-one".