13478791509 has 12 divisors (see below), whose sum is σ = 19495094476. Its totient is φ = 8973986112.

The previous prime is 13478791489. The next prime is 13478791511. The reversal of 13478791509 is 90519787431.

It is a happy number.

13478791509 is a `hidden beast` number, since 1 + 3 + 47 + 8 + 7 + 91 + 509 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 7858290609 + 5620500900 = 88647^2 + 74970^2 .

It is a de Polignac number, because none of the positive numbers 2^k-13478791509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13478791549) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 982384 + ... + 996009.

Almost surely, 2^13478791509 is an apocalyptic number.

It is an amenable number.

13478791509 is a deficient number, since it is larger than the sum of its proper divisors (6016302967).

13478791509 is a wasteful number, since it uses less digits than its factorization.

13478791509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1979156 (or 1979153 counting only the distinct ones).

The product of its (nonzero) digits is 1905120, while the sum is 54.

The spelling of 13478791509 in words is "thirteen billion, four hundred seventy-eight million, seven hundred ninety-one thousand, five hundred nine".