# Why Do Cicadas Emerge at Prime Intervals of 13 and 17 Years?

Mathematicians are fond of prime numbers. Infinitely numerous yet utterly unique, they play an integral role in number theory and a baffling one in such longstanding mysteries as Goldbach’s conjecture. Nature is partial to primes, as well, as demonstrated by the dramatic 13- and 17-year life cycles of periodic…

# The Math Behind Cicadas' Bizarre 17-Year Life Cycle

It makes sense that an animal might hid away in the ground while it's maturing, but 17 years is a long, seemingly random amount of time. But it's not like cicadas picked a number out of a hat and were stuck with it. There's a something specific about that number, and numberphile is sussing it out.

After a 17-year dormancy period, the U.S. East Coast is about to be overrun by over 30 billion cicadas. This preview for a documentary-in-the-making will show you what to expect — including a remarkable time-lapse of cicadas breaking through their exoskeletons.

# Crowdfund a book about Jack Kirby and a tale from The Obscure Cities

This week's crowdfunding takes us to a counter-Earth, and a never-before-translated story from François Schuiten and Benoît Peeters' Les Cités obscures. You can also back a documentary about cicadas, a comic starring a young gay superhero, or a book about Jack Kirby collected by his son.

# You won't believe how many cicadas are about to envelop the East Coast

No, really. Take a wild guess how many.

# Why do cicadas know prime numbers?

Cicadas incubate underground for long years. They emerge every 13 or 17 years to mate and make annoying noises when people are trying to sleep. Both 13 and 17 are prime numbers. What is it that makes cicadas come out during these years?

# This is what an office building covered in cicadas looks like

If you're one of those Harold Camping superfans who've waited your whole life for an Old Testament plague, might I suggest moving to Nashville? A fellow who works there recently filmed a solid six stories of them. Warning: video's loud.