202020202021 has 4 divisors (see below), whose sum is σ = 220385674944. Its totient is φ = 183654729100.

The previous prime is 202020201953. The next prime is 202020202031. The reversal of 202020202021 is 120202020202.

202020202021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 202020202021 - 2⁷ = 202020201893 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 202020201992 and 202020202010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (202020202031) 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, 9182736445 + ... + 9182736466.

It is an arithmetic number, because the mean of its divisors is an integer number (55096418736).

Almost surely, 2^202020202021 is an apocalyptic number.

It is an amenable number.

202020202021 is a deficient number, since it is larger than the sum of its proper divisors (18365472923).

202020202021 is a wasteful number, since it uses less digits than its factorization.

202020202021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18365472922.

The product of its (nonzero) digits is 64, while the sum is 13.

Adding to 202020202021 its reverse (120202020202), we get a palindrome (322222222223).

The spelling of 202020202021 in words is "two hundred two billion, twenty million, two hundred two thousand, twenty-one".