Q. Find the number of divisors of 1420.
✅ Correct Answer: (D)
12
Explanation:
1420 = 2 × 710
= 2 × 2 × 355
= 2² × 5 × 71
Number of divisors formula:
If N = pᵃ × qᵇ × rᶜ,
then Number of divisors = (a + 1)(b + 1)(c + 1)
For 1420:
1420 = 2² × 5¹ × 71¹
Number of divisors
= (2 + 1)(1 + 1)(1 + 1)
= 3 × 2 × 2
= 12
Answer: (D) 12
Explanation by: Mr. Dubey
1420 = 2 × 710
= 2 × 2 × 355
= 2² × 5 × 71
Number of divisors formula:
If N = pᵃ × qᵇ × rᶜ,
then Number of divisors = (a + 1)(b + 1)(c + 1)
For 1420:
1420 = 2² × 5¹ × 71¹
Number of divisors
= (2 + 1)(1 + 1)(1 + 1)
= 3 × 2 × 2
= 12
Answer: (D) 12