Posted by: Dave Richeson | August 25, 2009

## 867-5309; more than Jenny’s phone number

A few days ago I posted a video about the twin prime conjecture, which states that there are infinitely many primes that are two integers apart: 3 and 5, 5 and 7, 11 and 13, 101 and 103, 1607 and 1609…

Well, check this out. Type 8675309 into WolframAlpha and it says: “Jenny’s phone number.” (Har, har, har, we all know that song.)

At the top of the page it says: Assuming “8675309” is a phrase | Use as a number instead.

Click on that link and you’ll see the following interesting facts about 8675309.

1. 8675309 is a prime.
2. 8675309 is a twin prime (8675311 is also prime).
3. 8675309 is the hypotenuse of a (primitive) Pythagorean triple: 86753092 = 24602602+83191412.

That’s so cool! Who knew?!?!

As Tim Quinn points out, the Nova ScienceNOW song is the second song about twin primes. The first was by Tommy Tutone.

## Responses

1. Typo in your title… 367…?

• Oops! Thanks for pointing that out. It is fixed now.

• There’s also a typo in the second paragraph:
“Type 8765309 into WolframAlpha”
(dyslexic typo)
But the link’s correct — 8675309.

Very cool stuff, though!

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