21112020212021 has 4 divisors (see below), whose sum is σ = 21112769344992. Its totient is φ = 21111271079052.

The previous prime is 21112020211907. The next prime is 21112020212027. The reversal of 21112020212021 is 12021202021112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21112020212021 - 2¹⁰ = 21112020210997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112020212027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 374524211 + ... + 374580576.

It is an arithmetic number, because the mean of its divisors is an integer number (5278192336248).

Almost surely, 2^{21112020212021} is an apocalyptic number.

It is an amenable number.

21112020212021 is a deficient number, since it is larger than the sum of its proper divisors (749132971).

21112020212021 is an equidigital number, since it uses as much as digits as its factorization.

21112020212021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 749132970.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21112020212021 its reverse (12021202021112), we get a palindrome (33133222233133).

The spelling of 21112020212021 in words is "twenty-one trillion, one hundred twelve billion, twenty million, two hundred twelve thousand, twenty-one".