13131321 has 32 divisors (see below), whose sum is σ = 21577728. Its totient is φ = 6937920.

The previous prime is 13131319. The next prime is 13131329. The reversal of 13131321 is 12313131.

13131321 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 13131321 - 2¹ = 13131319 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 13131321.

It is not an unprimeable number, because it can be changed into a prime (13131329) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14535 + ... + 15411.

It is an arithmetic number, because the mean of its divisors is an integer number (674304).

Almost surely, 2^13131321 is an apocalyptic number.

It is an amenable number.

13131321 is a deficient number, since it is larger than the sum of its proper divisors (8446407).

13131321 is a wasteful number, since it uses less digits than its factorization.

13131321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 941.

The product of its digits is 54, while the sum is 15.

The square root of 13131321 is about 3623.7164624181. The cubic root of 13131321 is about 235.9225602955.

Adding to 13131321 its reverse (12313131), we get a palindrome (25444452).

The spelling of 13131321 in words is "thirteen million, one hundred thirty-one thousand, three hundred twenty-one".