TRB BT Assistant - Prime Numbers, Composite Numbers and Divisibility Online Test (MCQ Quiz)

1. Which of the following numbers is a prime number?

A) 4 B) 9 C) 11 D) 15

2. A number that has exactly two distinct positive divisors, 1 and itself, is called a:

A) Composite number B) Even number C) Prime number D) Odd number

3. Which of the following is the smallest composite number?

A) 1 B) 2 C) 3 D) 4

4. The number 1 is neither a prime number nor a:

A) Even number B) Odd number C) Composite number D) Natural number

5. Which of the following numbers is divisible by 2?

A) 13 B) 17 C) 22 D) 29

6. A number is divisible by 3 if the sum of its digits is divisible by:

A) 2 B) 3 C) 4 D) 5

7. Which of the following numbers is divisible by 5?

A) 123 B) 456 C) 780 D) 911

8. A number is divisible by 6 if it is divisible by both 2 and:

A) 3 B) 4 C) 5 D) 7

9. Which of the following numbers is divisible by 9?

A) 1234 B) 5678 C) 9018 D) 2345

10. The divisibility rule for 10 states that a number is divisible by 10 if its last digit is:

A) 1 B) 0 C) 5 D) Any even digit

11. Which of the following is NOT a prime number?

A) 2 B) 3 C) 5 D) 9

12. What is the prime factorization of 12?

A) 2 x 6 B) 3 x 4 C) 2 x 2 x 3 D) 2 x 3 x 3

13. A number that has more than two positive divisors is called a:

A) Prime number B) Composite number C) Perfect number D) Fibonacci number

14. Which prime number is an even number?

A) 0 B) 2 C) 4 D) 6

15. The number 17 is a:

A) Composite number B) Even number C) Prime number D) Square number

16. If a number leaves a remainder of 0 when divided by another number, it is said to be:

A) Prime B) Composite C) Divisible D) Even

17. Which of the following numbers is divisible by 4?

A) 123 B) 456 C) 789 D) 101

18. A number is divisible by 11 if the difference between the sum of digits at odd places and the sum of digits at even places is divisible by:

A) 3 B) 5 C) 11 D) 13

19. What is the sum of the digits of the number 345?

A) 10 B) 11 C) 12 D) 13

20. Which of the following is the smallest prime number?

A) 0 B) 1 C) 2 D) 3

21. The number 25 is a:

A) Prime number B) Composite number C) Even number D) Odd prime number

22. Which of the following numbers is divisible by 7?

A) 14 B) 15 C) 16 D) 18

23. A factor of a number is a number that divides it without leaving a:

A) Quotient B) Sum C) Remainder D) Product

24. Which of the following is a composite number?

A) 23 B) 29 C) 31 D) 33

25. The prime factorization of 30 is:

A) 2 x 3 x 5 B) 2 x 15 C) 3 x 10 D) 5 x 6

26. A number that is divisible by 2 is called an:

A) Odd number B) Prime number C) Even number D) Composite number

27. Which of the following numbers is divisible by 8? (A number is divisible by 8 if the number formed by its last three digits is divisible by 8)

A) 1234 B) 5678 C) 9016 D) 2345

28. The number 37 is a:

A) Composite number B) Even number C) Prime number D) Perfect number

29. Which of the following is NOT a divisor of 24?

A) 3 B) 5 C) 6 D) 8

30. A number is divisible by 12 if it is divisible by both 3 and:

A) 2 B) 4 C) 5 D) 6

31. What is the smallest odd prime number?

A) 1 B) 3 C) 5 D) 7

32. Which of the following is a prime number?

A) 51 B) 53 C) 57 D) 59

33. The number 100 is a:

A) Prime number B) Composite number C) Odd number D) Prime factor

34. Which of the following numbers is divisible by 11?

A) 121 B) 123 C) 125 D) 127

35. The sum of the digits of 789 is:

A) 21 B) 22 C) 23 D) 24

36. Which number is divisible by both 2 and 3?

A) 10 B) 12 C) 14 D) 16

37. The number 1 is:

A) Prime B) Composite C) Neither prime nor composite D) Both prime and composite

38. Which of the following is the largest prime number less than 50?

A) 41 B) 43 C) 47 D) 49

39. The prime factorization of 42 is:

A) 2 x 3 x 7 B) 6 x 7 C) 2 x 21 D) 3 x 14

40. A number is divisible by 9 if the sum of its digits is divisible by:

A) 3 B) 6 C) 9 D) 11

41. Which of the following is a composite number?

A) 13 B) 17 C) 19 D) 21

42. What is the prime factorization of 56?

A) 7 x 8 B) 2 x 2 x 2 x 7 C) 2 x 4 x 7 D) 4 x 14

43. A number is divisible by 5 if its last digit is 0 or:

A) 1 B) 2 C) 3 D) 5

44. Which of the following is a prime number?

A) 87 B) 91 C) 97 D) 99

45. If a number is divisible by 3 and 5, it is also divisible by:

A) 8 B) 10 C) 15 D) 30

46. The number 2 is:

A) An odd prime B) An even composite C) An even prime D) An odd composite

47. Which of the following numbers is divisible by 11? (Alternating sum of digits)

A) 2345 B) 3456 C) 4567 D) 5678

48. The number 64 is a:

A) Prime number B) Composite number C) Odd number D) Prime factor

49. Which of the following is NOT a divisor of 36?

A) 4 B) 7 C) 9 D) 12

50. A number is divisible by 7 if doubling the last digit and subtracting it from the remaining number results in a number divisible by:

A) 2 B) 3 C) 5 D) 7

Prime Numbers, Composite Numbers and Divisibility - Online Test

Test Results