11665971 has 8 divisors (see below), whose sum is σ = 17282960. Its totient is φ = 7777296.

The previous prime is 11665963. The next prime is 11666021. The reversal of 11665971 is 17956611.

It is a happy number.

11665971 is a `hidden beast` number, since 1 + 1 + 66 + 597 + 1 = 666.

It is not a de Polignac number, because 11665971 - 2³ = 11665963 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11665931) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 216010 + ... + 216063.

It is an arithmetic number, because the mean of its divisors is an integer number (2160370).

Almost surely, 2^11665971 is an apocalyptic number.

11665971 is a deficient number, since it is larger than the sum of its proper divisors (5616989).

11665971 is an equidigital number, since it uses as much as digits as its factorization.

11665971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432082 (or 432076 counting only the distinct ones).

The product of its digits is 11340, while the sum is 36.

The square root of 11665971 is about 3415.5484186291. The cubic root of 11665971 is about 226.7985624611.

The spelling of 11665971 in words is "eleven million, six hundred sixty-five thousand, nine hundred seventy-one".