20 squared

20² = 20 × 20 = 400

To square a number, multiply it by itself. 20 squared is written 20² or 20^2, and the answer is 400.

How to work out 20 squared

Direct: 20 × 20 = 400.
From the previous square: 19² = 361, and 20² = 361 + (2 × 20 − 1) = 361 + 39 = 400.

Related

20 cubed = 8,000
The square root of 400 is 20, so 400 is a perfect square.

Squares near 20

Number	Squared
16	256
17	289
18	324
19	361
21	441
22	484
23	529
24	576

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