1321231121 has 4 divisors (see below), whose sum is σ = 1509978432. Its totient is φ = 1132483812.

The previous prime is 1321231099. The next prime is 1321231141. The reversal of 1321231121 is 1211321231.

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 1321231121 - 2²² = 1317036817 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 1321231121.

It is not an unprimeable number, because it can be changed into a prime (1321231141) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 94373645 + ... + 94373658.

It is an arithmetic number, because the mean of its divisors is an integer number (377494608).

Almost surely, 2^1321231121 is an apocalyptic number.

It is an amenable number.

1321231121 is a deficient number, since it is larger than the sum of its proper divisors (188747311).

1321231121 is an equidigital number, since it uses as much as digits as its factorization.

1321231121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188747310.

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

The square root of 1321231121 is about 36348.7430456680. The cubic root of 1321231121 is about 1097.3022378778.

Adding to 1321231121 its reverse (1211321231), we get a palindrome (2532552352).

It can be divided in two parts, 1321231 and 121, that multiplied together give a palindrome (159868951).

The spelling of 1321231121 in words is "one billion, three hundred twenty-one million, two hundred thirty-one thousand, one hundred twenty-one".