CSATNumber System & SeriesSequence Pattern Reasoning2025

If N² = 12345678987654321, then how many digits does the number N have?

A

8

B

9

C

10

D

11

Correct Answer: Option B

Explanation

1. **Analyze the Number**: The number is $12345678987654321$. It is a palindrome that counts up to **9** and then back down to 1. 2. **Apply PYQ

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