Factorise a number or test primality by trial division

This type of question, asked 2 times: CDS 2 2021, CDS 1 2023. All 3 questions below, oldest first.

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Question 1
CDS 2 2021
1 $What are distinct prime factors of the number 26381 ?$
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Question 2
CDS 2 2021
14 $p$
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Question 3
CDS 1 2023
7 $Consider the following numbers : 1. 437 2. 797 3. 1073 How many of the above numbers are prime?$
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