Square of 27
27 squared equals 729. Squares appear in area calculations, the Pythagorean theorem, and statistics (variance uses squared distances).
Squares obey quiet rules. Divided by 9, a square only ever leaves 0, 1, 4 or 7 — 0 here. On the last digit, squares end only in 0, 1, 4, 5, 6 or 9, and 9 fits. Between its neighbors, 676 sits 53 below and 784 sits 55 above — the square ladder widens by exactly two at every step. An odd base keeps the square odd: 729 ends in an odd digit, as every odd square must. Two anchors most worth memorizing in this range are 12² = 144 and 15² = 225 — the odd-step rule above is why knowing them pays off, because from any anchor the next square is one step along this page's ladder.
| Expression | Value |
|---|---|
| 27² | 729 |
Frequently asked questions
What is 27 squared?
27 squared is 729, because 27 × 27 = 729. The exponent 2 is why it is written 27².
What is 28 squared, next to 27²?
28² = 784, which is 55 more than 27² = 729. Each step up adds double the base plus one.
Where do squares show up in real problems?
Area of a square with side 27, distance in the Pythagorean theorem, and variance in statistics all use squared values.