11691 has 8 divisors (see below), whose sum is σ = 17360.
Its totient is φ = 7776.
The previous prime is 11689. The next prime is 11699. The reversal of 11691 is 19611.
It is not a de Polignac number, because 11691 - 21 = 11689 is a prime.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (11699) 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, 190 + ... + 243.
It is an arithmetic number, because the mean of its divisors is an integer number (2170).
211691 is an apocalyptic number.
11691 is a deficient number, since it is larger than the sum of its proper divisors (5669).
11691 is an equidigital number, since it uses as much as digits as its factorization.
11691 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 442 (or 436 counting only the distinct ones).
The product of its digits is 54, while the sum is 18.
The square root of 11691 is about 108.1249277456.
The cubic root of 11691 is about 22.6960643167.
The spelling of 11691 in words is "eleven thousand, six hundred ninety-one".