Prime Numbers and Prime Factorisation

7 is a prime number because its only divisors are 1 and 7.

2 is the smallest prime number. It is the only even prime number because its only divisors are 1 and 2.

15 is not a prime number because it is divisible by 3 and 5, making it a composite number.

The prime factorisation of 36 is $2^2 \times 3^2$, as 36 can be broken down into the product of these prime factors: $2 \times 2 \times 3 \times 3$.

The prime factorisation of 144 is $2^4 \times 3^2$. This is because 144 can be broken down into $2 \times 2 \times 2 \times 2 \times 3 \times 3$.

The correct prime factorisation of 360 is $2^3 \times 3^2 \times 5$. This is because 360 can be broken down into $2 \times 2 \times 2 \times 3 \times 3 \times 5$.