221323323121 has 4 divisors (see below), whose sum is σ = 225499234932. Its totient is φ = 217147411312.

The previous prime is 221323323101. The next prime is 221323323149. The reversal of 221323323121 is 121323323122.

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 114419827600 + 106903495521 = 338260^2 + 326961^2 .

It is a cyclic number.

It is not a de Polignac number, because 221323323121 - 2¹⁹ = 221322798833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221323323101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2087955826 + ... + 2087955931.

It is an arithmetic number, because the mean of its divisors is an integer number (56374808733).

Almost surely, 2^221323323121 is an apocalyptic number.

It is an amenable number.

221323323121 is a deficient number, since it is larger than the sum of its proper divisors (4175911811).

221323323121 is an equidigital number, since it uses as much as digits as its factorization.

221323323121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4175911810.

The product of its digits is 2592, while the sum is 25.

Adding to 221323323121 its reverse (121323323122), we get a palindrome (342646646243).

Subtracting from 221323323121 its reverse (121323323122), we obtain a palindrome (99999999999).

The spelling of 221323323121 in words is "two hundred twenty-one billion, three hundred twenty-three million, three hundred twenty-three thousand, one hundred twenty-one".