Prime Factorization and Repeated Division

Prime Factorization and Repeated Division

This video explains how to write a number as a product of prime numbers, or "prime factorization." One such method is through factor trees; students can take a number like 36 and make two branches representing 2*18 as one step in the process. Then, they can make another two branches off 18 to write that as 3*6. Last, they can make another two branches of 6 to write that as 3*2. In the end, we re-write 36 as 2*3*3*2. An analogous process is to use repeated division, where we keep dividing by primes like 2, 3, and 5, until we can't divide anymore. The values that go in evenly form the prime factorization for the given value.

Some terms used in this video are:

Factor tree: a way to break a number down into smaller numbers through products.
Prime number: a number whose only factors are 1 and itself, for example, 2, 3, 5, 7, etc.

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[EsmeOB-P]

Hello! I have a question. When using repeated division, do you need to use a prime number for the divisor? E.g, when you used 36 divided by 2 for your example, and 2 is a prime number, was that a coincidence or does it actually need to be a prime number?