Forto En Numeros... that's it in Esperanto, I think.
Forto En Numeroj.
Yeah, I hate the -j for plurals, too. Hey, how about an Esperanto fork! Scamanto.
Nombroj - numbers [of things]; cardinal numbers
Numeroj - numerals; ordinal numbers
Ciferoj - ciphers, figures, digits
If the emphasis is on many people, it should be nombroj. If the emphasis is on encryption, it should be ciferoj.
If... everything's in order, it should be numeroj?