Three great questions.
How old is the universe? The universe is approximately 13.8 billion years old. 13,800,000,000. in numbers.
How old is the earth? 4.543 billion years old. 4.543, 000,000. in numbers.
How long have humans been around? about 200,000 years.
When were mans earliest ancestors around? between 7 to 6 million years ago. 7,000,000 – 6,000,000 Sahelanthropus tchadensis is one of the oldest known species in the human family tree.
Great information on The Smithsonian Institute National Museum of Natural history. http://humanorigins.si.edu/evidence/human-fossils/species