13231321 has 4 divisors (see below), whose sum is σ = 14009652. Its totient is φ = 12452992.

The previous prime is 13231319. The next prime is 13231331. The reversal of 13231321 is 12313231.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7080921 + 6150400 = 2661^2 + 2480^2 .

It is a cyclic number.

It is not a de Polignac number, because 13231321 - 2¹ = 13231319 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13231295 and 13231304.

It is not an unprimeable number, because it can be changed into a prime (13231331) 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, 389140 + ... + 389173.

It is an arithmetic number, because the mean of its divisors is an integer number (3502413).

Almost surely, 2^13231321 is an apocalyptic number.

It is an amenable number.

13231321 is a deficient number, since it is larger than the sum of its proper divisors (778331).

13231321 is an equidigital number, since it uses as much as digits as its factorization.

13231321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 778330.

The product of its digits is 108, while the sum is 16.

The square root of 13231321 is about 3637.4882817681. The cubic root of 13231321 is about 236.5199264484.

Adding to 13231321 its reverse (12313231), we get a palindrome (25544552).

The spelling of 13231321 in words is "thirteen million, two hundred thirty-one thousand, three hundred twenty-one".