13667809 has 3 divisors (see below), whose sum is σ = 13671507. Its totient is φ = 13664112.

The previous prime is 13667803. The next prime is 13667827. The reversal of 13667809 is 90876631.

The square root of 13667809 is 3697.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 1221025 + 12446784 = 1105^2 + 3528^2 .

It is not a de Polignac number, because 13667809 - 2⁵ = 13667777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13667803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 1849 + ... + 5545.

It is an arithmetic number, because the mean of its divisors is an integer number (4557169).

Almost surely, 2^13667809 is an apocalyptic number.

13667809 is the 3697-th square number.

13667809 is the 1849-th centered octagonal number.

It is an amenable number.

13667809 is a deficient number, since it is larger than the sum of its proper divisors (3698).

13667809 is an frugal number, since it uses more digits than its factorization.

13667809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7394 (or 3697 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 40.

The cubic root of 13667809 is about 239.0926911818.

The spelling of 13667809 in words is "thirteen million, six hundred sixty-seven thousand, eight hundred nine".