1,980
1,980 is a composite number, even, a calendar year.
Notable events — 1980 AD
- Feb 13 The Winter Olympics open in Lake Placid, New York.
- Feb 22 The US hockey team upsets the Soviets in the "Miracle on Ice" at the Lake Placid Olympics.
- May 4 Yugoslav President Josip Broz Tito dies after 35 years in power.
- May 18 Mount St. Helens erupts in Washington State, killing 57.
- Nov 4 Ronald Reagan defeats Jimmy Carter in the US presidential election.
- Dec 8 John Lennon is shot dead outside his New York City apartment.
Events compiled from Wikipedia ↗ · Licensed CC BY-SA 4.0
Year facts
- Year type
-
Leap year
Divisible by 4 and not by 100; February has 29 days.
- Days in year
- 366
- ISO weeks
- 52
- Started on
-
Tuesday
January 1, 1980
- Ended on
-
Wednesday
December 31, 1980
- Friday the 13ths
-
1
One Friday the 13th this year.
- Easter Sunday
-
April 6
Sunday, April 6, 1980
- Decade
-
1980s
1980–1989
- Century
-
20th century
1901–2000
- Millennium
-
2nd millennium
1001–2000
- Years ago
-
46
46 years before 2026.
- US presidential election
-
Yes
US holds a presidential election in years divisible by 4 starting from 1788.
- Summer Olympics
- Yes
- Winter Olympics
-
Yes
Held in the same year as the Summer Games until 1992.
In other calendars
- Hebrew
-
5740 / 5741 AM
Rosh Hashanah falls in September/October.
- Islamic Hijri
-
1400 / 1401 AH
Lunar calendar; year spans differ from Gregorian.
- Chinese
-
Year of the zodiac:Metal zodiac:Monkey
Sexagenary cycle position 57 of 60. Lunar new year falls in late January / mid-February.
- Buddhist Era
-
2523 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
- Persian Solar Hijri
-
1358 / 1359 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
- Ethiopian
-
1972 / 1973 ET
Year boundary at Enkutatash (September 11/12).
- Indian National (Saka)
-
1902 / 1901 Saka
Indian national calendar; year starts in March.
- Japanese
-
Shōwa 55
Reign-era counting from the start of each emperor's reign.
Properties
- Parity
- Even
- Digit count
- 4
- Digit sum
- 18
- Digit product
- 0
- Digital root
- 9
- Palindrome
- No
- Bit width
- 11 bits
- Reversed
- 891
- Flips to (rotate 180°)
- 861
- Recamán's sequence
- a(3,791) = 1,980
- Square (n²)
- 3,920,400
- Cube (n³)
- 7,762,392,000
- Divisor count
- 36
- σ(n) — sum of divisors
- 6,552
- φ(n) — Euler's totient
- 480
- Sum of prime factors
- 26
Primality
Prime factorization: 2 2 × 3 2 × 5 × 11
Divisors & multiples
Sums & aliquot sequence
Representations
- In words
- one thousand nine hundred eighty
- Ordinal
- 1980th
- Roman numeral
- MCMLXXX
- Binary
- 11110111100
- Octal
- 3674
- Hexadecimal
- 0x7BC
- Base64
- B7w=
- One's complement
- 63,555 (16-bit)
Historical numeral systems
- Babylonian (base 60)
- 𒌋𒌋𒌋𒁹𒁹𒁹 ·
- Egyptian hieroglyphic
- 𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆
- Greek (Milesian)
- ͵αϡπʹ
- Mayan (base 20)
- 𝋤·𝋳·𝋠
- Chinese
- 一千九百八十
- Chinese (financial)
- 壹仟玖佰捌拾
Digit at this position in famous constants
- π — Pi (π)
- Digit 1,980 = 4
- e — Euler's number (e)
- Digit 1,980 = 1
- φ — Golden ratio (φ)
- Digit 1,980 = 3
- √2 — Pythagoras's (√2)
- Digit 1,980 = 6
- ln 2 — Natural log of 2
- Digit 1,980 = 7
- γ — Euler-Mascheroni (γ)
- Digit 1,980 = 9
Also seen as
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 1980, here are decompositions:
- 7 + 1973 = 1980
- 29 + 1951 = 1980
- 31 + 1949 = 1980
- 47 + 1933 = 1980
- 67 + 1913 = 1980
- 73 + 1907 = 1980
- 79 + 1901 = 1980
- 101 + 1879 = 1980
Showing the first eight; more decompositions exist.
As an unsigned 32-bit integer, this is the IPv4 address 0.0.7.188.
- Address
- 0.0.7.188
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.7.188
Unspecified address (0.0.0.0/8) — "this network" placeholder.
The digit sequence 1980 first appears in π at position 6,633 of the decimal expansion (the 6,633ordinal-suffix:rd digit after the integer 3).
Search range: the first 1,000,000 fractional digits of π. Any 6-digit-or-shorter string is virtually guaranteed to appear in there — the more interesting signal is the position.