21220320201 has 4 divisors (see below), whose sum is σ = 28293760272. Its totient is φ = 14146880132.

The previous prime is 21220320157. The next prime is 21220320211. The reversal of 21220320201 is 10202302212.

It is a happy number.

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 21220320201 - 2²⁹ = 20683449289 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21220320211) 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, 3536720031 + ... + 3536720036.

It is an arithmetic number, because the mean of its divisors is an integer number (7073440068).

Almost surely, 2^21220320201 is an apocalyptic number.

It is an amenable number.

21220320201 is a deficient number, since it is larger than the sum of its proper divisors (7073440071).

21220320201 is an equidigital number, since it uses as much as digits as its factorization.

21220320201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7073440070.

The product of its (nonzero) digits is 96, while the sum is 15.

Adding to 21220320201 its reverse (10202302212), we get a palindrome (31422622413).

The spelling of 21220320201 in words is "twenty-one billion, two hundred twenty million, three hundred twenty thousand, two hundred one".