980

[Library]  ISBN-980 is the International Standard Book Number for books published in Venezuela.

 

[Tech.]  The “number system” code of an EAN-13 barcode for refund receipts.

 

981

[Library]  ISBN-981 and ISBN-9971 are the International Standard Book Number codes for books published in Singapore.

 

[Math.]  Sum 327+654 = 981 is one of only 4 cases that the equality: n+2n = 3n use each of 9 digits 1-9 once. Others: 192+384 = 576, 219+438 = 657 and 273+546 = 819.

 

981 & 982

[Tech.]  The “number system” code of an EAN-13 barcode for common currency coupons: 99, 981 and 982.

 

982

[Library]  ISBN-982 is the International Standard Book Number for books published in South Pacific Ocean countries/states: Cook Islands, Fiji, Kiribati, Marshall Islands, Federal States of Micronesia, Nauru, New Caledonia, Niue, Palau, Saint Barthelemy, Solomon Islands, Tokelau, Tonga, Tuvalu, Vanuatu and Western Samoa.

 

983

[Library]  ISBN-983 and ISBN-967 are the International Standard Book Number codes for books published in Malaysia.

 

[Math.]  A prime number. The largest prime number of 3 different digits.

 

984

[Library]  ISBN-984 is the International Standard Book Number for books published in Bangladesh.

 

985

[Library]  ISBN-985 is the International Standard Book Number for books published in Belarus (before 1991, Byelorussia). Also, ISBN-5 for the former USSR.

 

[Math.]  The 4th square number that is the sum of squares of 2 consecutive numbers: 970,225 = 9852 = 6962+6972. The nth root number is 6 times the (n–1)th root minus the (n–2)th root: 1, 52, 292, 1692, 9852

Or in other words:  (696, 697, 985) is the 4th Pythagorean triple (lengths of 3 sides of a right triangle), where 2 sides are consecutive integers.

 

[Phone]   The emergency telephone number dialing within Slovenia.

 

986

[Library]  ISBN-986 and ISBN-957 are the International Standard Book Number codes for books published in Taiwan.


[Math.]  986 = 19+28+36.

  

987 (separate page)

 

988

[Math.] (232+767 = 999 = 212+787)

2322 = 053,824 & 053+824 = 877

7672 = 588,289 & 588+289 = 877

and

2122 = 044,944 & 044+944 = 988

7872 = 619,369 & 619+369 = 988.

 

[Library]  ISBN-988 and ISBN-962 are the International Standard Book Number codes for books published in Hong Kong.

 

989

[Library]  ISBN-989 and ISBN-972 are the International Standard Book Number codes for books published in Portugal.

 

[Math.]  9892 = 978,121 = (978+12–1)2.

 

[Phone]  The largest number assigned for an area code of an NANPA/U.S. telephone number: for Upper Central Michigan (Mt. Pleasant, Saginaw), as of the year 2005. (NANPA: North American Numbering Plan Administration)

 

980-989

[Library]  Numbers 900-999 are the first 3 digits in Dewey Decimal Classification System call numbers for library books in History and Geography. Numbers 980-989 are for books in South American History.