8165

8165 is a natural number that follows 8164 and precedes 8166. It is odd and composite. Its prime factorization is 5 × 23 × 71, which makes 8165 squarefree and a sphenic number—the product of three distinct primes.

The positive divisors of 8165 are 1, 5, 23, 71, 115, 355, 1633, and 8165. Accordingly, the number of divisors is eight, and Euler's totient function gives φ(8165) = 6160 (calculated as (5−1)(23−1)(71−1) = 4×22×70).

In decimal terms, the sum of digits is 20, so it is not divisible by 3 or 9, but it is divisible by 5. In binary, 8165 is 1111111100101; in hexadecimal, it is 0x1FE5; in octal, it is 17745.

Geometrically or numerically, 8165 lies between 2^12 = 4096 and 2^13 = 8192, placing it just below the next power of two. In number theory, 8165 is often cited as an example of a sphenic number—being the product of three distinct primes with exactly eight positive divisors.