21200021212201 has 4 divisors (see below), whose sum is σ = 22830792074692. Its totient is φ = 19569250349712.

The previous prime is 21200021212157. The next prime is 21200021212211. The reversal of 21200021212201 is 10221212000212.

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 11911637352976 + 9288383859225 = 3451324^2 + 3047685^2 .

It is a cyclic number.

It is not a de Polignac number, because 21200021212201 - 2¹⁵ = 21200021179433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21200021212211) 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, 815385431226 + ... + 815385431251.

It is an arithmetic number, because the mean of its divisors is an integer number (5707698018673).

Almost surely, 2^{21200021212201} is an apocalyptic number.

It is an amenable number.

21200021212201 is a deficient number, since it is larger than the sum of its proper divisors (1630770862491).

21200021212201 is a wasteful number, since it uses less digits than its factorization.

21200021212201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1630770862490.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21200021212201 its reverse (10221212000212), we get a palindrome (31421233212413).

The spelling of 21200021212201 in words is "twenty-one trillion, two hundred billion, twenty-one million, two hundred twelve thousand, two hundred one".