20212111021 has 4 divisors (see below), whose sum is σ = 20283532192. Its totient is φ = 20140689852.

The previous prime is 20212111013. The next prime is 20212111103. The reversal of 20212111021 is 12011121202.

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 20212111021 - 2³ = 20212111013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20212110992 and 20212111010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20212111721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35710161 + ... + 35710726.

It is an arithmetic number, because the mean of its divisors is an integer number (5070883048).

Almost surely, 2^20212111021 is an apocalyptic number.

It is an amenable number.

20212111021 is a deficient number, since it is larger than the sum of its proper divisors (71421171).

20212111021 is an equidigital number, since it uses as much as digits as its factorization.

20212111021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71421170.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 20212111021 its reverse (12011121202), we get a palindrome (32223232223).

The spelling of 20212111021 in words is "twenty billion, two hundred twelve million, one hundred eleven thousand, twenty-one".