21112020201121 has 4 divisors (see below), whose sum is σ = 21112056788292. Its totient is φ = 21111983613952.

The previous prime is 21112020201113. The next prime is 21112020201143. The reversal of 21112020201121 is 12110202021112.

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 12329480504896 + 8782539696225 = 3511336^2 + 2963535^2 .

It is a cyclic number.

It is not a de Polignac number, because 21112020201121 - 2³ = 21112020201113 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21112020201095 and 21112020201104.

It is not an unprimeable number, because it can be changed into a prime (21112020201191) 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, 17413936 + ... + 18586801.

It is an arithmetic number, because the mean of its divisors is an integer number (5278014197073).

Almost surely, 2^{21112020201121} is an apocalyptic number.

It is an amenable number.

21112020201121 is a deficient number, since it is larger than the sum of its proper divisors (36587171).

21112020201121 is an equidigital number, since it uses as much as digits as its factorization.

21112020201121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36587170.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21112020201121 its reverse (12110202021112), we get a palindrome (33222222222233).

The spelling of 21112020201121 in words is "twenty-one trillion, one hundred twelve billion, twenty million, two hundred one thousand, one hundred twenty-one".