11809681915 has 4 divisors (see below), whose sum is σ = 14171618304. Its totient is φ = 9447745528.

The previous prime is 11809681879. The next prime is 11809681927. The reversal of 11809681915 is 51918690811.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 11809681915 - 2¹³ = 11809673723 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1180968187 + ... + 1180968196.

It is an arithmetic number, because the mean of its divisors is an integer number (3542904576).

Almost surely, 2^11809681915 is an apocalyptic number.

11809681915 is a deficient number, since it is larger than the sum of its proper divisors (2361936389).

11809681915 is an equidigital number, since it uses as much as digits as its factorization.

11809681915 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2361936388.

The product of its (nonzero) digits is 155520, while the sum is 49.

The spelling of 11809681915 in words is "eleven billion, eight hundred nine million, six hundred eighty-one thousand, nine hundred fifteen".