Prime factorization is when you break down the factors of 5 to just the prime factors and expressing 5 as a product of those prime factors.
In this case, because 5 is a prime number, we can simply state the primary factorization as 5.
For most numbers, we would take the smallest prime factor that is larger than 1 to start to break down the focus number. In this case, the smallest prime factor larger than 1 is 5.
5 ÷ 5 = 1
If we divide 5 by 5, we simply get 1, which can’t be broken down any further.
So, the prime factorization of 5 is just 5.