11809605187 has 4 divisors (see below), whose sum is σ = 11839055976. Its totient is φ = 11780154400.

The previous prime is 11809605163. The next prime is 11809605239. The reversal of 11809605187 is 78150690811.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78150690811 = 467 ⋅167346233.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11809605187 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11809605887) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14724793 + ... + 14725594.

It is an arithmetic number, because the mean of its divisors is an integer number (2959763994).

Almost surely, 2^11809605187 is an apocalyptic number.

11809605187 is a deficient number, since it is larger than the sum of its proper divisors (29450789).

11809605187 is an equidigital number, since it uses as much as digits as its factorization.

11809605187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29450788.

The product of its (nonzero) digits is 120960, while the sum is 46.

The spelling of 11809605187 in words is "eleven billion, eight hundred nine million, six hundred five thousand, one hundred eighty-seven".