11987809 has 8 divisors (see below), whose sum is σ = 12152160. Its totient is φ = 11824896.

The previous prime is 11987783. The next prime is 11987837. The reversal of 11987809 is 90878911.

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 11987809 - 2⁷ = 11987681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11987609) 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, 34374 + ... + 34720.

It is an arithmetic number, because the mean of its divisors is an integer number (1519020).

Almost surely, 2^11987809 is an apocalyptic number.

It is an amenable number.

11987809 is a deficient number, since it is larger than the sum of its proper divisors (164351).

11987809 is a wasteful number, since it uses less digits than its factorization.

11987809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 719.

The product of its (nonzero) digits is 36288, while the sum is 43.

The square root of 11987809 is about 3462.3415487210. The cubic root of 11987809 is about 228.8652932897.

The spelling of 11987809 in words is "eleven million, nine hundred eighty-seven thousand, eight hundred nine".