11665056165561 has 40 divisors (see below), whose sum is σ = 17470508419584. Its totient is φ = 7756663692960.

The previous prime is 11665056165551. The next prime is 11665056165569. The reversal of 11665056165561 is 16556165056611.

11665056165561 is a `hidden beast` number, since 1 + 1 + 6 + 65 + 0 + 5 + 6 + 16 + 5 + 561 = 666.

It is not a de Polignac number, because 11665056165561 - 2¹¹ = 11665056163513 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 11665056165498 and 11665056165507.

It is not an unprimeable number, because it can be changed into a prime (11665056165569) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 115528680 + ... + 115629606.

Almost surely, 2^{11665056165561} is an apocalyptic number.

It is an amenable number.

11665056165561 is a deficient number, since it is larger than the sum of its proper divisors (5805452254023).

11665056165561 is a wasteful number, since it uses less digits than its factorization.

11665056165561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104603 (or 104594 counting only the distinct ones).

The product of its (nonzero) digits is 4860000, while the sum is 54.

The spelling of 11665056165561 in words is "eleven trillion, six hundred sixty-five billion, fifty-six million, one hundred sixty-five thousand, five hundred sixty-one".