11965 has 4 divisors (see below), whose sum is σ = 14364. Its totient is φ = 9568.

The previous prime is 11959. The next prime is 11969. The reversal of 11965 is 56911.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1764 + 10201 = 42^2 + 101^2 .

It is a cyclic number.

It is not a de Polignac number, because 11965 - 2⁵ = 11933 is a prime.

It is a super-2 number, since 2×11965² = 286322450, which contains 22 as substring.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11969) 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, 1192 + ... + 1201.

It is an arithmetic number, because the mean of its divisors is an integer number (3591).

2¹¹⁹⁶⁵ is an apocalyptic number.

It is an amenable number.

11965 is a deficient number, since it is larger than the sum of its proper divisors (2399).

11965 is an equidigital number, since it uses as much as digits as its factorization.

11965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2398.

The product of its digits is 270, while the sum is 22.

The square root of 11965 is about 109.3846424321. The cubic root of 11965 is about 22.8720048434.

The spelling of 11965 in words is "eleven thousand, nine hundred sixty-five".