We find the prime factorization of each number:
- 54 = \( 2^1 \times 3^3 \)
- 288 = \( 2^5 \times 3^2 \)
- 360 = \( 2^3 \times 3^2 \times 5^1 \)
Now, taking the **minimum power** of each common factor:
\[
HCF = 2^1 \times 3^2
\]
\[
= 2 \times 9 = 18
\]
Thus, the HCF is 18.