MathsFreePrintable
Whole Numbers and Primes
A free maths worksheet ready for your classroom. Open in Kuraplan to grab the print-ready PDF, customize it for your students, or generate a fresh version in seconds.

Whole Numbers and Primes
📚 Part 1: Understanding Whole Numbers and Primes
1. What are whole numbers? Write your definition below:
2. Circle all the whole numbers from this list:
-3, 0, 2.5, 7, 15, -8, 100, 3/4, 42, 0.25
3. A prime number is a whole number greater than 1 that has exactly _____ factors.
one
two
three
four
4. Which of these numbers are prime? Check all that apply:
2
9
11
15
17
21
🔍 Part 2: Prime and Composite Numbers
5. Complete the table by writing "Prime" or "Composite" for each number:
13: ____________
20: ____________
23: ____________
28: ____________
29: ____________
6. Use the Sieve of Eratosthenes method to find all prime numbers from 2 to 30. Cross out the composite numbers and circle the primes:
2 3 4 5 6 7 8 9 10
11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30
7. List all the prime numbers you found from 2 to 30:
🌟 Part 3: Real-World Application
8. Prime numbers are used in computer security and internet banking to keep information safe. Why do you think prime numbers are useful for creating secret codes? Explain your thinking:
9. Challenge: Find the smallest prime number greater than 50. Show your working:
About This Worksheet
Free in Kuraplan
Sign up free, grab the PDF, and customize it for your class.
Print-Ready
Formatted for standard paper. Clean layout, easy to read.
AI-Generated
Created with Kuraplan's AI, designed for real classroom use.
For Teachers & Parents
Use in classrooms, for homework, tutoring, or homeschool.
Need a custom version of this worksheet?
Kuraplan's AI generates custom worksheets in seconds — differentiated for every learner, aligned to your curriculum.
Generate Custom Worksheets — Free No credit card Curriculum-aligned Under 60 seconds
More Maths Worksheets

Year 9
Fractions Parts of Whole
Free
Year 8
Working with Positive and Negative Numbers
Free
Year 9
Decimal Numbers Bingo
Free
Year 7
Percentage and Whole Problems
Free
Year 1–6
Māori Numbers 1-10
Free
Year 1
Teen Numbers Exploration
Free
Year 3–4
Partitioning Numbers for Subtraction
Free
Year 5–6