11591 has 4 divisors (see below), whose sum is σ = 11832. Its totient is φ = 11352.

The previous prime is 11587. The next prime is 11593. The reversal of 11591 is 19511.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19511 = 109 ⋅179.

It is a cyclic number.

It is not a de Polignac number, because 11591 - 2² = 11587 is a prime.

It is a Duffinian number.

It is a plaindrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11593) 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, 20 + ... + 153.

It is an arithmetic number, because the mean of its divisors is an integer number (2958).

2¹¹⁵⁹¹ is an apocalyptic number.

11591 is a deficient number, since it is larger than the sum of its proper divisors (241).

11591 is an equidigital number, since it uses as much as digits as its factorization.

11591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240.

The product of its digits is 45, while the sum is 17.

The square root of 11591 is about 107.6615065843. The cubic root of 11591 is about 22.6311680018.

The spelling of 11591 in words is "eleven thousand, five hundred ninety-one".