last number should be a Prime number
21
All the numbers are prime
If completed correctly, the bottom branch of a factor tree will be the prime factorization of the number at the top.
When the lowest branch consists entirely of prime numbers.
17, being a prime number, has one prime factor, itself. Whether you call that one branch or no branches, it won't be a tree.
A factor tree is a way to notate the process of finding the prime factorization. If completed successfully, the bottom row (branch) will display the prime factorization of the number you started with.
factor tree of 216
IT IS PRIME there is no factor tree
Factor tree of 204
The factor tree of 50:5025,25,5,25025,25,5,2
83 is prime. No tree.
The prime factor tree of 280 is:140,270,2,235,2,2,27,5,2,2,2