13288321 has 4 divisors (see below), whose sum is σ = 13425412. Its totient is φ = 13151232.

The previous prime is 13288313. The next prime is 13288343. The reversal of 13288321 is 12388231.

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 9678321 + 3610000 = 3111^2 + 1900^2 .

It is a cyclic number.

It is not a de Polignac number, because 13288321 - 2³ = 13288313 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 13288321.

It is not an unprimeable number, because it can be changed into a prime (13288021) 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, 68400 + ... + 68593.

It is an arithmetic number, because the mean of its divisors is an integer number (3356353).

Almost surely, 2^13288321 is an apocalyptic number.

It is an amenable number.

13288321 is a deficient number, since it is larger than the sum of its proper divisors (137091).

13288321 is an equidigital number, since it uses as much as digits as its factorization.

13288321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137090.

The product of its digits is 2304, while the sum is 28.

The square root of 13288321 is about 3645.3149383832. The cubic root of 13288321 is about 236.8590793457.

The spelling of 13288321 in words is "thirteen million, two hundred eighty-eight thousand, three hundred twenty-one".