221121321013 has 4 divisors (see below), whose sum is σ = 224235705888. Its totient is φ = 218006936140.

The previous prime is 221121320989. The next prime is 221121321053. The reversal of 221121321013 is 310123121122.

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, and also an emirpimes, since its reverse is a distinct semiprime: 310123121122 = 2 ⋅155061560561.

It is a cyclic number.

It is not a de Polignac number, because 221121321013 - 2¹³ = 221121312821 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 (221121321053) 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, 1557192331 + ... + 1557192472.

It is an arithmetic number, because the mean of its divisors is an integer number (56058926472).

Almost surely, 2^221121321013 is an apocalyptic number.

It is an amenable number.

221121321013 is a deficient number, since it is larger than the sum of its proper divisors (3114384875).

221121321013 is an equidigital number, since it uses as much as digits as its factorization.

221121321013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3114384874.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 221121321013 its reverse (310123121122), we get a palindrome (531244442135).

The spelling of 221121321013 in words is "two hundred twenty-one billion, one hundred twenty-one million, three hundred twenty-one thousand, thirteen".