165601005161111 has 16 divisors (see below), whose sum is σ = 187900169673216. Its totient is φ = 144796696631136.

The previous prime is 165601005161099. The next prime is 165601005161143. The reversal of 165601005161111 is 111161500106561.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-165601005161111 is a prime.

It is a super-3 number, since 3×165601005161111³ (a number of 44 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165601005061111) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2688559085 + ... + 2688620678.

It is an arithmetic number, because the mean of its divisors is an integer number (11743760604576).

Almost surely, 2^{165601005161111} is an apocalyptic number.

165601005161111 is a deficient number, since it is larger than the sum of its proper divisors (22299164512105).

165601005161111 is a wasteful number, since it uses less digits than its factorization.

165601005161111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5377179902.

The product of its (nonzero) digits is 5400, while the sum is 35.

Adding to 165601005161111 its reverse (111161500106561), we get a palindrome (276762505267672).

The spelling of 165601005161111 in words is "one hundred sixty-five trillion, six hundred one billion, five million, one hundred sixty-one thousand, one hundred eleven".