165811113 has 12 divisors (see below), whose sum is σ = 257928580. Its totient is φ = 102037536.

The previous prime is 165811109. The next prime is 165811123. The reversal of 165811113 is 311118561.

It is a happy number.

165811113 is a `hidden beast` number, since 1 + 658 + 1 + 1 + 1 + 1 + 3 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 110502144 + 55308969 = 10512^2 + 7437^2 .

It is not a de Polignac number, because 165811113 - 2² = 165811109 is a prime.

It is not an unprimeable number, because it can be changed into a prime (165811103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 708478 + ... + 708711.

Almost surely, 2^165811113 is an apocalyptic number.

165811113 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

165811113 is a deficient number, since it is larger than the sum of its proper divisors (92117467).

165811113 is a wasteful number, since it uses less digits than its factorization.

165811113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1417208 (or 1417205 counting only the distinct ones).

The product of its digits is 720, while the sum is 27.

The square root of 165811113 is about 12876.7664030998. The cubic root of 165811113 is about 549.3779336042.

Adding to 165811113 its reverse (311118561), we get a palindrome (476929674).

The spelling of 165811113 in words is "one hundred sixty-five million, eight hundred eleven thousand, one hundred thirteen".