201021220112021 has 4 divisors (see below), whose sum is σ = 201215819551692. Its totient is φ = 200826620672352.

The previous prime is 201021220111979. The next prime is 201021220112071. The reversal of 201021220112021 is 120211022120102.

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 114601606785796 + 86419613326225 = 10705214^2 + 9296215^2 .

It is a cyclic number.

It is not a de Polignac number, because 201021220112021 - 2²⁶ = 201021153003157 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 (201021220112071) 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, 97299718286 + ... + 97299720351.

It is an arithmetic number, because the mean of its divisors is an integer number (50303954887923).

Almost surely, 2^{201021220112021} is an apocalyptic number.

It is an amenable number.

201021220112021 is a deficient number, since it is larger than the sum of its proper divisors (194599439671).

201021220112021 is a wasteful number, since it uses less digits than its factorization.

201021220112021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194599439670.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 201021220112021 its reverse (120211022120102), we get a palindrome (321232242232123).

The spelling of 201021220112021 in words is "two hundred one trillion, twenty-one billion, two hundred twenty million, one hundred twelve thousand, twenty-one".