200020010021 has 4 divisors (see below), whose sum is σ = 215406164652. Its totient is φ = 184633855392.

The previous prime is 200020009991. The next prime is 200020010033. The reversal of 200020010021 is 120010020002.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 120010020002 = 2 ⋅60005010001.

It can be written as a sum of positive squares in 2 ways, for example, as 135140788225 + 64879221796 = 367615^2 + 254714^2 .

It is a cyclic number.

It is not a de Polignac number, because 200020010021 - 2¹⁰ = 200020008997 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 200020009990 and 200020010008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (200020010081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7693077296 + ... + 7693077321.

It is an arithmetic number, because the mean of its divisors is an integer number (53851541163).

Almost surely, 2^200020010021 is an apocalyptic number.

It is an amenable number.

200020010021 is a deficient number, since it is larger than the sum of its proper divisors (15386154631).

200020010021 is a wasteful number, since it uses less digits than its factorization.

200020010021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15386154630.

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

Adding to 200020010021 its reverse (120010020002), we get a palindrome (320030030023).

The spelling of 200020010021 in words is "two hundred billion, twenty million, ten thousand, twenty-one".