12861809 has 8 divisors (see below), whose sum is σ = 13718880. Its totient is φ = 12015936.

The previous prime is 12861791. The next prime is 12861817. The reversal of 12861809 is 90816821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12861809 - 2⁸ = 12861553 is a prime.

It is a super-2 number, since 2×12861809² = 330852261504962, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12861889) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 359 + ... + 5084.

It is an arithmetic number, because the mean of its divisors is an integer number (1714860).

Almost surely, 2^12861809 is an apocalyptic number.

It is an amenable number.

12861809 is a deficient number, since it is larger than the sum of its proper divisors (857071).

12861809 is a wasteful number, since it uses less digits than its factorization.

12861809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5599.

The product of its (nonzero) digits is 6912, while the sum is 35.

The square root of 12861809 is about 3586.3364315134. The cubic root of 12861809 is about 234.2973367333.

The spelling of 12861809 in words is "twelve million, eight hundred sixty-one thousand, eight hundred nine".