20100001121021 has 4 divisors (see below), whose sum is σ = 20590245050844. Its totient is φ = 19609757191200.

The previous prime is 20100001121009. The next prime is 20100001121027. The reversal of 20100001121021 is 12012110000102.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7639065820996 + 12460935300025 = 2763886^2 + 3530005^2 .

It is a cyclic number.

It is not a de Polignac number, because 20100001121021 - 2¹⁰ = 20100001119997 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20100001120993 and 20100001121011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20100001121027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 245121964850 + ... + 245121964931.

It is an arithmetic number, because the mean of its divisors is an integer number (5147561262711).

Almost surely, 2^{20100001121021} is an apocalyptic number.

It is an amenable number.

20100001121021 is a deficient number, since it is larger than the sum of its proper divisors (490243929823).

20100001121021 is an equidigital number, since it uses as much as digits as its factorization.

20100001121021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 490243929822.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 20100001121021 its reverse (12012110000102), we get a palindrome (32112111121123).

The spelling of 20100001121021 in words is "twenty trillion, one hundred billion, one million, one hundred twenty-one thousand, twenty-one".