#;(#);Z\E\RO!;W\h\at i\s \"@\"\?

which will print positive numbers with a leading plus sign, negative
numbers surround by parentheses instead of having a leading minus
sign, zero will be spelled out and, for any non-number, you will be
asked what is it.

First magic and now plain trickery, what next <g

See what you can learn to do by reading Harry Potter books.<g

Just to clarify, the plus sign was accidentally omitted when I copied the
format pattern string from my spreadsheet to the posting I sent. The above
format pattern string should have been this one...

+#;(#);Z\E\RO!;W\h\at i\s \"@\"\?

so that the positive numbers would have the leading plus sign I said they
would.

Rick