A Briefly Perfect Number
Yesterday, the Earth hit a neat milestone. The global population reached 7,777,777,777! It quickly passed, and is already nearing 7.78 billion, but it may take 10 years before the population reaches 8,888,888,888. It took until the year 18 hundred, for the world population to reach 1 billion. The 2nd billion took just 130 years. The last billion only took 12 years!