9945

9945 is a natural number that lies between 9944 and 9946. In decimal notation, it is an odd composite number with a digit sum of 27 and a digital root of 9.

Its prime factorization is 9945 = 3^2 × 5 × 13 × 17, making it divisible by 9, 5, 15, and 45, among other divisors. The number has 24 positive divisors, and the sum of its divisors is 19656.

Since 9945 = 9 × 1105 and 1105 = 5 × 13 × 17, the integer 1105 is a Carmichael number. Therefore, 9945 is a multiple of a Carmichael number, a property of interest in number theory.

In base 2, 9945 is represented as 10011011011001_2.

Overall, 9945 is a composite, highly factorable integer with a high divisibility profile and a notable connection to Carmichael numbers through its factor 1105.