9645

9645 is a natural number that lies between 9644 and 9646. It is an odd and composite integer that can be factored into primes as 3 × 5 × 643.

In base-10 arithmetic, 9645 is divisible by 3 and by 5, hence by 15, but it is not divisible by smaller primes such as 7, 11, or 13. The sum of its decimal digits is 9 + 6 + 4 + 5 = 24, so 9645 is not a Harshad (Niven) number, which would require the number to be divisible by the sum of its digits.

Base representations of 9645 include: in binary, 9645 equals 10010110101101₂; in octal, it is 22655₈; and in hexadecimal, it is 25B9₁₆.

From a number-theoretic perspective, the prime factorization 9645 = 3 × 5 × 643 shows that 9645 has three distinct prime factors. The sum of all divisors of 9645 is (1 + 3)(1 + 5)(1 + 643) = 15456, which means the sum of proper divisors is 15456 − 9645 = 5811. Since this sum is less than the number itself, 9645 is classified as a deficient number.