What's Your Favorite Number?

British author Alex Bellos is known for his book 'Alex's Adventures in Numberland,' which is published in the US with the title 'Here's Looking At Euclid.'
Alex wants to know your favorite number and why. His survey is part of a project he is researching concerning how humans relate to numbers.

Seven is still the global favorite, dominating every class, nationality, gender, religion and age category. Seven is being chased by a small pack of prime numbers, especially 11 and 13.