1321321121 has 4 divisors (see below), whose sum is σ = 1330071744. Its totient is φ = 1312570500.

The previous prime is 1321321117. The next prime is 1321321129. The reversal of 1321321121 is 1211231231.

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 1321321121 - 2² = 1321321117 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1321321121.

It is not an unprimeable number, because it can be changed into a prime (1321321129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4375085 + ... + 4375386.

It is an arithmetic number, because the mean of its divisors is an integer number (332517936).

Almost surely, 2^1321321121 is an apocalyptic number.

It is an amenable number.

1321321121 is a deficient number, since it is larger than the sum of its proper divisors (8750623).

1321321121 is an equidigital number, since it uses as much as digits as its factorization.

1321321121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8750622.

The product of its digits is 72, while the sum is 17.

The square root of 1321321121 is about 36349.9810316319. The cubic root of 1321321121 is about 1097.3271527615.

Adding to 1321321121 its reverse (1211231231), we get a palindrome (2532552352).

The spelling of 1321321121 in words is "one billion, three hundred twenty-one million, three hundred twenty-one thousand, one hundred twenty-one".