13131809 has 4 divisors (see below), whose sum is σ = 13584660. Its totient is φ = 12678960.

The previous prime is 13131791. The next prime is 13131851. The reversal of 13131809 is 90813131.

13131809 is digitally balanced in base 3, 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 2795584 + 10336225 = 1672^2 + 3215^2 .

It is a cyclic number.

It is not a de Polignac number, because 13131809 - 2⁸ = 13131553 is a prime.

It is a super-2 number, since 2×13131809² = 344888815224962, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (13131509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 226382 + ... + 226439.

It is an arithmetic number, because the mean of its divisors is an integer number (3396165).

Almost surely, 2^13131809 is an apocalyptic number.

It is an amenable number.

13131809 is a deficient number, since it is larger than the sum of its proper divisors (452851).

13131809 is an equidigital number, since it uses as much as digits as its factorization.

13131809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 452850.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 13131809 is about 3623.7837959790. The cubic root of 13131809 is about 235.9254827936.

The spelling of 13131809 in words is "thirteen million, one hundred thirty-one thousand, eight hundred nine".