253 = 11 x 23.
253 has a unique representation as a sum of three squares: 253 = 32 + 102 + 122.
253 is the sum of three positive cubes: 253 = 53 + 43 + 43.
25 - 3 is a prime number.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjrqm8VHnZZYNx-ZuPrxsXU3SGECxT-DJbssShKKRlRzRZGe_tmQQrU3zUGrnx15LvyvOqDEDfB6_fya6p5QIv3XFqrKkknjKz5xTN5aMSUTv8uOgiI3R2Ke3wTaDrhDItPN5MgKuv2DXY/s400/n0253.jpg)
253 is a star number. The nth star number is given by the formula 6n(n - 1) + 1.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhW-ISvRWU6n2SaZN4JMt3s5-AoqzxhfHF1hlsIRJDItu8ilQq1jBojApP1WGsfVREAmeW7uhFfkHMbcS5VgtOPvUeEx_SATP3iBnNvr3Ujiz6-fvjdzoaod2DQuGOf6mcwf2-yDBnbL2A/s400/starnumber.jpg)
NGC 253, also known as the Silver Coin Galaxy or the Sculptor Galaxy, is a large spiral galaxy in the constellation Sculptor.
25 - 3 is a prime number.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjrqm8VHnZZYNx-ZuPrxsXU3SGECxT-DJbssShKKRlRzRZGe_tmQQrU3zUGrnx15LvyvOqDEDfB6_fya6p5QIv3XFqrKkknjKz5xTN5aMSUTv8uOgiI3R2Ke3wTaDrhDItPN5MgKuv2DXY/s400/n0253.jpg)
253 is a star number. The nth star number is given by the formula 6n(n - 1) + 1.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhW-ISvRWU6n2SaZN4JMt3s5-AoqzxhfHF1hlsIRJDItu8ilQq1jBojApP1WGsfVREAmeW7uhFfkHMbcS5VgtOPvUeEx_SATP3iBnNvr3Ujiz6-fvjdzoaod2DQuGOf6mcwf2-yDBnbL2A/s400/starnumber.jpg)
NGC 253, also known as the Silver Coin Galaxy or the Sculptor Galaxy, is a large spiral galaxy in the constellation Sculptor.
Source: Wikipedia