Strengths
Search- Oh my they own 70 something percent of total market share. They are a verb for goodness sakes that means the word they profit most from.
Android- 80% of global market share. A brilliant move to give it away for free to equipment makers, and gather data on users and maintain its near monopoly of search.
Affiliate program- Adsense is the #1 money maker for most websites on the net. This drives a lot of traffic to Google and their ad partners. No one comes close to touching it.
Management- Android + YouTube purchased were turned into mega hits, and were both forward thinking. They now dominate their respective areas, and benefit each other. They comprise a large part of Google's ecosystem.
incredibly loyal employees who love working there. They want the company to succeed. Ample anecdotes on the net to read about this.
Pipeline of products coming out. Google invests a tremendous amount into R+D. More details below
Cash- in excess of 60 billion in CA$H on the balance cushions the price you pay for the shares.
They have the best engineers on the world, and everyone wants to work for them.