20100001221021 has 16 divisors (see below), whose sum is σ = 27320446226304. Its totient is φ = 13140052296384.

The previous prime is 20100001221011. The next prime is 20100001221059. The reversal of 20100001221021 is 12012210000102.

It is not a de Polignac number, because 20100001221021 - 2²⁵ = 20099967666589 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20100001220988 and 20100001221006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20100001221011) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33928066 + ... + 34515411.

It is an arithmetic number, because the mean of its divisors is an integer number (1707527889144).

Almost surely, 2^{20100001221021} is an apocalyptic number.

It is an amenable number.

20100001221021 is a deficient number, since it is larger than the sum of its proper divisors (7220445005283).

20100001221021 is a wasteful number, since it uses less digits than its factorization.

20100001221021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68445380.

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

Adding to 20100001221021 its reverse (12012210000102), we get a palindrome (32112211221123).

The spelling of 20100001221021 in words is "twenty trillion, one hundred billion, one million, two hundred twenty-one thousand, twenty-one".