11665307543121 has 16 divisors (see below), whose sum is σ = 17500695801600. Its totient is φ = 7678430280144.

The previous prime is 11665307543117. The next prime is 11665307543129. The reversal of 11665307543121 is 12134570356611.

11665307543121 is a `hidden beast` number, since 1 + 1 + 6 + 6 + 530 + 75 + 43 + 1 + 2 + 1 = 666.

It is not a de Polignac number, because 11665307543121 - 2² = 11665307543117 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11665307543129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2734481586 + ... + 2734485851.

It is an arithmetic number, because the mean of its divisors is an integer number (1093793487600).

Almost surely, 2^{11665307543121} is an apocalyptic number.

It is an amenable number.

11665307543121 is a deficient number, since it is larger than the sum of its proper divisors (5835388258479).

11665307543121 is an equidigital number, since it uses as much as digits as its factorization.

11665307543121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5468967525 (or 5468967519 counting only the distinct ones).

The product of its (nonzero) digits is 453600, while the sum is 45.

Adding to 11665307543121 its reverse (12134570356611), we get a palindrome (23799877899732).

The spelling of 11665307543121 in words is "eleven trillion, six hundred sixty-five billion, three hundred seven million, five hundred forty-three thousand, one hundred twenty-one".