1231132321 has 4 divisors (see below), whose sum is σ = 1235142832. Its totient is φ = 1227121812.

The previous prime is 1231132319. The next prime is 1231132327. The reversal of 1231132321 is 1232311321.

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 1231132321 - 2¹ = 1231132319 is a prime.

It is a super-3 number, since 3×1231132321³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1231132327) 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, 2004795 + ... + 2005408.

It is an arithmetic number, because the mean of its divisors is an integer number (308785708).

Almost surely, 2^1231132321 is an apocalyptic number.

It is an amenable number.

1231132321 is a deficient number, since it is larger than the sum of its proper divisors (4010511).

1231132321 is an equidigital number, since it uses as much as digits as its factorization.

1231132321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4010510.

The product of its digits is 216, while the sum is 19.

The square root of 1231132321 is about 35087.4952226573. The cubic root of 1231132321 is about 1071.7699535256.

Adding to 1231132321 its reverse (1232311321), we get a palindrome (2463443642).

The spelling of 1231132321 in words is "one billion, two hundred thirty-one million, one hundred thirty-two thousand, three hundred twenty-one".