325 (three hundred [and] twenty-five) is the natural number following 324 and preceding 326.
In mathematics
- 325 is the smallest number to be the sum of two squares in 3 different ways: 1<sup>2</sup> + 18<sup>2</sup>, 6<sup>2</sup> + 17<sup>2</sup> and 10<sup>2</sup> + 15<sup>2</sup>.
- 325 is the smallest (and only known) 3-hyperperfect number.
- 325 is the smallest odd unprimeable number.
References