221312613121 has 4 divisors (see below), whose sum is σ = 230934900672. Its totient is φ = 211690325572.

The previous prime is 221312613113. The next prime is 221312613169. The reversal of 221312613121 is 121316213122.

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 221312613121 - 2³ = 221312613113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221312613521) 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, 4811143741 + ... + 4811143786.

It is an arithmetic number, because the mean of its divisors is an integer number (57733725168).

Almost surely, 2^221312613121 is an apocalyptic number.

It is an amenable number.

221312613121 is a deficient number, since it is larger than the sum of its proper divisors (9622287551).

221312613121 is an equidigital number, since it uses as much as digits as its factorization.

221312613121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9622287550.

The product of its digits is 864, while the sum is 25.

Adding to 221312613121 its reverse (121316213122), we get a palindrome (342628826243).

The spelling of 221312613121 in words is "two hundred twenty-one billion, three hundred twelve million, six hundred thirteen thousand, one hundred twenty-one".