When looking at the hiragana ぬ (nu), ね (ne), and る (ru) one notices a small circle in the symbols. In fact that circle is the only difference when comparing them with the hiragana め (me), れ (re) and ろ ...
Japanese uses both native and Chinese numbering numbering systems, the Sino-Japanese pronunciations being いち, に, さん, etc. and the native being ひと, ふた, み, etc. For the most part they are used for ...