A page of the Numeropedia - the Special Encyclopedia of Numbers
[Calendar] The last year of the 8th century.
[Education] The best possible SAT (Scholastic Aptitude Test) Verbal score and SAT Mathematics score.
[Education] The best possible GRE (Graduate Record Examinations) Verbal score and Quantitative score, on the scale 200-800, with 10-point increments.
[History] The approximate length (miles) of the Santa Fe Trail, ending at Santa Fe, New Mexico.
[Measure] The customary volume (ml, milliliters) of a wine bottle in the U.S. and Bordeaux, France is 705 ml. Before 1945, French wine bottles were mostly 800ml, commonly for Burgundy, Champagne and Rhone.
[Phone] The original area code for the toll-free (or WATS: Wide Area Telecommunications Service) telephone number dialing within the U.S. and Canada.
[Sport] The standard ranges of swimming/tracking competitions (meters): 50, 100, 200, 400, 800 and 1500. Also, for tracking: 2000, 3000, 5000 and 10000.
[Tech.] The light sensitivity (speed) of most commercially popular camera films: ISO 100-200-400-800.
[World] The ISO country code for Uganda. (ISO-3166)
[Calendar] The first year of the 9th century.
[Sport] One of the popular beginning scores to play down to exactly zero in a dartboard game tournament: 301, 501, 601, 801 and 1001…, which always end with 01. Higher scores are usually played by teams.
[Phone] The only telephone area code for the state of Vermont, U.S.
[Math.] (Sequence of numbers 80…032 = 640…0480…09)
8032 = 644,809 = (–6+4–4+809)2
8033 = 517,781,627 = (5–1+7+781+6–2+7)3.
[World] The ISO country code for Ukraine. (ISO-3166)
[Library] ISBN-0-805 is the International Standard Book Number for books published by Henry Holt & Company.
[Math.] (Sequence of numbers 80…052 = 640…080…025)
8052 = 648,025 = (–6+4+802+5)2.
13×93 = 1,209 = 31×39
26×93 = 2,418 = 62×39
13×62 = 806 = 31×26.
[World] The ISO country code for Macedonia, (was Republic of Yugoslav). (ISO-3166)
[Phone] The only telephone area code for the state of Hawaii, U.S.
[Math.] A prime number.
[Phone] The telephone area codes for the Dominican Republic (within U.S./NANPA) are 809 and 829.
[Library] Numbers 800-899 are the first 3 digits in Dewey Decimal Classification System call numbers for library books in Literature. Numbers 800-809 are for general & dictionary works.