11811 has 8 divisors (see below), whose sum is σ = 16384. Its totient is φ = 7560.

The previous prime is 11807. The next prime is 11813.

It is a happy number.

11811 is nontrivially palindromic in base 10.

11811 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 11811 - 2² = 11807 is a prime.

11811 is a strobogrammatic number because it is the same when read upside-down.

It is a Duffinian number.

11811 is a lucky number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 11811.

It is not an unprimeable number, because it can be changed into a prime (11813) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30 + ... + 156.

It is an arithmetic number, because the mean of its divisors is an integer number (2048).

2¹¹⁸¹¹ is an apocalyptic number.

11811 is a deficient number, since it is larger than the sum of its proper divisors (4573).

11811 is a wasteful number, since it uses less digits than its factorization.

11811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161.

The product of its digits is 8, while the sum is 12.

The square root of 11811 is about 108.6784247217. The cubic root of 11811 is about 22.7734532518.

The spelling of 11811 in words is "eleven thousand, eight hundred eleven".