Prime factorization is when you break down the factors of 7 to just the prime factors and expressing 7 as a product of those prime factors.
In this case, because 7 is a prime number, we can simply state the primary factorization as 7.
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 7.
7 ÷ 7 = 1
If we divide 7 by 7, we simply get 1, which can’t be broken down any further.
So, the prime factorization of 7 is just 7.