12665 has 8 divisors (see below), whose sum is σ = 16200. Its totient is φ = 9472.

The previous prime is 12659. The next prime is 12671. The reversal of 12665 is 56621.

12665 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (12659) and next prime (12671).

It can be written as a sum of positive squares in 4 ways, for example, as 784 + 11881 = 28^2 + 109^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 12665 - 2⁶ = 12601 is a prime.

It is a plaindrome in base 14.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11 + ... + 159.

It is an arithmetic number, because the mean of its divisors is an integer number (2025).

2¹²⁶⁶⁵ is an apocalyptic number.

It is an amenable number.

12665 is a deficient number, since it is larger than the sum of its proper divisors (3535).

12665 is a wasteful number, since it uses less digits than its factorization.

12665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171.

The product of its digits is 360, while the sum is 20.

The square root of 12665 is about 112.5388821697. The cubic root of 12665 is about 23.3096130828.

Subtracting 12665 from its reverse (56621), we obtain a triangular number (43956 = T₂₉₆).

It can be divided in two parts, 126 and 65, that added together give a palindrome (191).

The spelling of 12665 in words is "twelve thousand, six hundred sixty-five".