13278865 has 4 divisors (see below), whose sum is σ = 15934644. Its totient is φ = 10623088.

The previous prime is 13278851. The next prime is 13278869. The reversal of 13278865 is 56887231.

13278865 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 2143296 + 11135569 = 1464^2 + 3337^2 .

It is a cyclic number.

It is not a de Polignac number, because 13278865 - 2⁷ = 13278737 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13278869) 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, 1327882 + ... + 1327891.

It is an arithmetic number, because the mean of its divisors is an integer number (3983661).

Almost surely, 2^13278865 is an apocalyptic number.

It is an amenable number.

13278865 is a deficient number, since it is larger than the sum of its proper divisors (2655779).

13278865 is an equidigital number, since it uses as much as digits as its factorization.

13278865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2655778.

The product of its digits is 80640, while the sum is 40.

The square root of 13278865 is about 3644.0177002863. The cubic root of 13278865 is about 236.8028828573.

The spelling of 13278865 in words is "thirteen million, two hundred seventy-eight thousand, eight hundred sixty-five".