There is a free online tool for spell checking in several languages including Spanish. It is a net site called Spellcheck. Type in whole paragraphs or simple words and it will return the results quickly.
One thousand (1000) is mil in Spanish.
Six-point-one
100
That's un amor.
The term "no one" is "nadie." (NAH-dee-ay)
One-thousand one-hundered fif-teen
Most forms of notepad have no spell-checking. One way to check is to copy the text into a browser that has spell-checking, fix it there, then paste it back. Or you can copy and paste into MS Word and also spell check your document from there.
cuarenta y uno (or -a if it feminine)
One term for it is "Centro comercial."
You could say "No hay nadie allí".
Nochebuena, in one word.
== == One has spell check and one does not.