11566 has 4 divisors (see below), whose sum is σ = 17352. Its totient is φ = 5782.

The previous prime is 11551. The next prime is 11579. The reversal of 11566 is 66511.

11566 is an esthetic number in base 11, because in such base its adjacent digits differ by 1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 66511 = 227 ⋅293.

It is a plaindrome in base 10.

It is a nialpdrome in base 11.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2890 + ... + 2893.

It is an arithmetic number, because the mean of its divisors is an integer number (4338).

2¹¹⁵⁶⁶ is an apocalyptic number.

11566 is a deficient number, since it is larger than the sum of its proper divisors (5786).

11566 is an equidigital number, since it uses as much as digits as its factorization.

11566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5785.

The product of its digits is 180, while the sum is 19.

The square root of 11566 is about 107.5453392760. The cubic root of 11566 is about 22.6148856432.

Subtracting 11566 from its reverse (66511), we obtain a palindrome (54945).

It can be divided in two parts, 115 and 66, that added together give a palindrome (181).

The spelling of 11566 in words is "eleven thousand, five hundred sixty-six".