11661565165161 has 8 divisors (see below), whose sum is σ = 15552289789824. Its totient is φ = 7772608658640.

The previous prime is 11661565165099. The next prime is 11661565165171. The reversal of 11661565165161 is 16156156516611.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 11661565165161 - 2⁹ = 11661565164649 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (11661565165171) 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, 442014145 + ... + 442040526.

It is an arithmetic number, because the mean of its divisors is an integer number (1944036223728).

Almost surely, 2^{11661565165161} is an apocalyptic number.

It is an amenable number.

11661565165161 is a deficient number, since it is larger than the sum of its proper divisors (3890724624663).

11661565165161 is an equidigital number, since it uses as much as digits as its factorization.

11661565165161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 884059071.

The product of its digits is 972000, while the sum is 51.

The spelling of 11661565165161 in words is "eleven trillion, six hundred sixty-one billion, five hundred sixty-five million, one hundred sixty-five thousand, one hundred sixty-one".