200001020021 has 4 divisors (see below), whose sum is σ = 218182930944. Its totient is φ = 181819109100.

The previous prime is 200001019993. The next prime is 200001020039. The reversal of 200001020021 is 120020100002.

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 200001020021 - 2²⁶ = 199933911157 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 200001019990 and 200001020008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (200001023021) 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, 9090955445 + ... + 9090955466.

It is an arithmetic number, because the mean of its divisors is an integer number (54545732736).

Almost surely, 2^200001020021 is an apocalyptic number.

It is an amenable number.

200001020021 is a deficient number, since it is larger than the sum of its proper divisors (18181910923).

200001020021 is a wasteful number, since it uses less digits than its factorization.

200001020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18181910922.

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

Adding to 200001020021 its reverse (120020100002), we get a palindrome (320021120023).

The spelling of 200001020021 in words is "two hundred billion, one million, twenty thousand, twenty-one".