The ⟨W⟩ is silent now, but it wasn't until 1500 or so. Back then the word was pronounced /two:/; it would almost rhyme with contemporary "toe". But then that /o:/ became /u:/ (the modern pronunciation), due to the Great Vowel Shift, and since /w/ and /u/ are really similar they fused together.
@[email protected] mentioned that in a few associated words that ⟨W⟩ letter still represents an actual /w/ phoneme, note how the following vowel is different - that blocked the "fusion".
I wonder if perhaps an older dialect used to pronounce the W. Lots of words have changed spelling or pronunciation over the years, so I'm curious if that might be the case with "two", too.
Twelve's root is in meaning "two left". And similarly eleven's origin is meaning "one left". In both cases left over from ten, the base unit of counting.
Okay, unless you want to taunt someone into trying to hijack your Google account or track your info, you should edit your comment link to remove the ? and everything after that.