---
title: 2.685 is (almost) everywhere - Numberphile
link: https://www.youtube.com/watch?v=-mXaU3N9e8Y
source: youtube-com-numberphile
published: 2026-08-22T14:09:57Z
updated: 2026-08-29T14:55:09Z
first_seen: 2026-09-08T10:17:10.166315Z
authors:
- Numberphile
summary: "Richard Elwes discusses Khinchin's constant which underlies 100% of numbers (but not every number). More about Jane Street Internships at https://jane-st.co/internships2027-Numberphile (episode sponsor). More links & stuff in full description below ↓↓↓\n\nExtra footage from this interview: https://youtu.be/jl8Fk7PPeOc\n\nWe previously touched on the constant in this video from 2013: https://www.youtube.com/watch?v=VDD6FDhKCYA\n\nMore Richard on Numberphile: https://www.youtube.com/playlist?list=PLt5AfwLFPxWI42WXh1jnv51jHrcjatrk8\n\nMore about Richard Elwes (who is based at the University of Leeds): https://richardelwes.co.uk/ \n\nRichard's latest book Huge Numbers\nAmazon (affiliate links)...\nUK: https://amzn.to/4bSZA8v\nUS: https://amzn.to/4v3CIMp\n\nPatreon: http://www.patreon.com/numberphile\n\nNumberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet\n\nWe are also grateful for support from the Ben Delo Foundation - https://delo.org/\n\nNUMBERPHILE\nWebsite: http://www.numberphile.com/\n\nVideo by Brady Haran & Pete McPartlan\n\nNumberphile T-Shirts and Merch: https://teespring.com/stores/numberphile\n\nBrady's videos subreddit: http://www.reddit.com/r/BradyHaran/\n\nBrady's latest videos across all channels: http://www.bradyharanblog.com/\n\nSign up for (occasional) emails: http://eepurl.com/YdjL9"
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Richard Elwes discusses Khinchin's constant which underlies 100% of numbers (but not every number). More about Jane Street Internships at https://jane-st.co/internships2027-Numberphile (episode sponsor). More links & stuff in full description below ↓↓↓

Extra footage from this interview: https://youtu.be/jl8Fk7PPeOc

We previously touched on the constant in this video from 2013: https://www.youtube.com/watch?v=VDD6FDhKCYA

More Richard on Numberphile: https://www.youtube.com/playlist?list=PLt5AfwLFPxWI42WXh1jnv51jHrcjatrk8

More about Richard Elwes (who is based at the University of Leeds): https://richardelwes.co.uk/

Richard's latest book Huge Numbers\
Amazon (affiliate links)...\
UK: https://amzn.to/4bSZA8v\
US: https://amzn.to/4v3CIMp

Patreon: http://www.patreon.com/numberphile

Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet

We are also grateful for support from the Ben Delo Foundation - https://delo.org/

NUMBERPHILE\
Website: http://www.numberphile.com/

Video by Brady Haran & Pete McPartlan

Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile

Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/

Brady's latest videos across all channels: http://www.bradyharanblog.com/

Sign up for (occasional) emails: http://eepurl.com/YdjL9