20021100200221 has 4 divisors (see below), whose sum is σ = 20093378540572. Its totient is φ = 19948821859872.

The previous prime is 20021100200191. The next prime is 20021100200287. The reversal of 20021100200221 is 12200200112002.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4161032899321 + 15860067300900 = 2039861^2 + 3982470^2 .

It is a cyclic number.

It is not a de Polignac number, because 20021100200221 - 2¹⁷ = 20021100069149 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 (20021100200291) 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, 36139169760 + ... + 36139170313.

It is an arithmetic number, because the mean of its divisors is an integer number (5023344635143).

Almost surely, 2^{20021100200221} is an apocalyptic number.

It is an amenable number.

20021100200221 is a deficient number, since it is larger than the sum of its proper divisors (72278340351).

20021100200221 is an equidigital number, since it uses as much as digits as its factorization.

20021100200221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72278340350.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 20021100200221 its reverse (12200200112002), we get a palindrome (32221300312223).

The spelling of 20021100200221 in words is "twenty trillion, twenty-one billion, one hundred million, two hundred thousand, two hundred twenty-one".