11665161 has 8 divisors (see below), whose sum is σ = 17281760. Its totient is φ = 7776756.

The previous prime is 11665151. The next prime is 11665187. The reversal of 11665161 is 16156611.

11665161 is a `hidden beast` number, since 1 + 1 + 6 + 651 + 6 + 1 = 666.

It is not a de Polignac number, because 11665161 - 2⁶ = 11665097 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 432043 = 11665161 / (1 + 1 + 6 + 6 + 5 + 1 + 6 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11665151) 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, 215995 + ... + 216048.

It is an arithmetic number, because the mean of its divisors is an integer number (2160220).

Almost surely, 2^11665161 is an apocalyptic number.

It is an amenable number.

11665161 is a deficient number, since it is larger than the sum of its proper divisors (5616599).

11665161 is an equidigital number, since it uses as much as digits as its factorization.

11665161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 432052 (or 432046 counting only the distinct ones).

The product of its digits is 1080, while the sum is 27.

The square root of 11665161 is about 3415.4298411767. The cubic root of 11665161 is about 226.7933132599.

The spelling of 11665161 in words is "eleven million, six hundred sixty-five thousand, one hundred sixty-one".