11661516165 has 32 divisors (see below), whose sum is σ = 20206005120. Its totient is φ = 5708964096.

The previous prime is 11661516151. The next prime is 11661516169. The reversal of 11661516165 is 56161516611.

11661516165 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 11661516165 - 2⁶ = 11661516101 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11661516169) 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 31 ways as a sum of consecutive naturals, for example, 132142 + ... + 201951.

It is an arithmetic number, because the mean of its divisors is an integer number (631437660).

Almost surely, 2^11661516165 is an apocalyptic number.

11661516165 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

11661516165 is a deficient number, since it is larger than the sum of its proper divisors (8544488955).

11661516165 is a wasteful number, since it uses less digits than its factorization.

11661516165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 334293.

The product of its digits is 32400, while the sum is 39.

The spelling of 11661516165 in words is "eleven billion, six hundred sixty-one million, five hundred sixteen thousand, one hundred sixty-five".