You can either write the number, which is the same in German, 63, or the words for the number: drei und sechzig.
Sixty-three.
You can write any whole number as a fraction, by writing "1" in the denominator; in this case, 63/1. This can't be simplified any more, unless you write it again as a whole number, without the denominator of 1.
1 and 63/100
23 63/1000
6.6 = 63/5
63,024,511
63/10
It is: 7 and 63/100 as a mixed number
6 cubed = 63
3 and 3/20
Six tens plus three ones