1) Complete the equation below
Replace each question mark with a mathematical sign. Plus, minus, multiply and divide can each be used once only. For the Maths purists, each part of the equation should be done in order from left to right. No BODMAS here.
6 ? 5 ? 7 ? 2 ? 3 = 25
2) What makes this number unique:
8,549,176,320?