1165005161 has 4 divisors (see below), whose sum is σ = 1165122132. Its totient is φ = 1164888192.

The previous prime is 1165005151. The next prime is 1165005221. The reversal of 1165005161 is 1615005611.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1615005611 = 79 ⋅20443109.

It can be written as a sum of positive squares in 2 ways, for example, as 377136400 + 787868761 = 19420^2 + 28069^2 .

It is a cyclic number.

It is not a de Polignac number, because 1165005161 - 2⁶ = 1165005097 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1165005161.

It is not an unprimeable number, because it can be changed into a prime (1165005151) 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 3 ways as a sum of consecutive naturals, for example, 41996 + ... + 63981.

It is an arithmetic number, because the mean of its divisors is an integer number (291280533).

Almost surely, 2^1165005161 is an apocalyptic number.

It is an amenable number.

1165005161 is a deficient number, since it is larger than the sum of its proper divisors (116971).

1165005161 is a wasteful number, since it uses less digits than its factorization.

1165005161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116970.

The product of its (nonzero) digits is 900, while the sum is 26.

The square root of 1165005161 is about 34132.1719349941. The cubic root of 1165005161 is about 1052.2266161239.

The spelling of 1165005161 in words is "one billion, one hundred sixty-five million, five thousand, one hundred sixty-one".