21100202010021 has 12 divisors (see below), whose sum is σ = 28674440906048. Its totient is φ = 13801389988464.

The previous prime is 21100202010007. The next prime is 21100202010059. The reversal of 21100202010021 is 12001020200112.

It is not a de Polignac number, because 21100202010021 - 2³⁴ = 21083022140837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21100202009979 and 21100202010006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100202010521) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1251931885 + ... + 1251948738.

Almost surely, 2^{21100202010021} is an apocalyptic number.

It is an amenable number.

21100202010021 is a deficient number, since it is larger than the sum of its proper divisors (7574238896027).

21100202010021 is an equidigital number, since it uses as much as digits as its factorization.

21100202010021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2503880732 (or 2503880679 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21100202010021 its reverse (12001020200112), we get a palindrome (33101222210133).

The spelling of 21100202010021 in words is "twenty-one trillion, one hundred billion, two hundred two million, ten thousand, twenty-one".