1,990
1,990 is a composite number, even, a calendar year.
Notable events — 1990 AD
- Jan 3 Manuel Noriega surrenders to US forces after the invasion of Panama.
- Feb 11 Nelson Mandela is released from prison after 27 years.
- Mar 11 Lithuania declares independence from the Soviet Union.
- Aug 2 Iraq invades Kuwait, triggering the Gulf War.
- Oct 3 East and West Germany reunify.
Events compiled from Wikipedia ↗ · Licensed CC BY-SA 4.0
Year facts
- Year type
-
Common year
Standard 365-day year; not divisible by 4 (or divisible by 100 but not 400).
- Days in year
- 365
- ISO weeks
- 52
- Started on
-
Monday
January 1, 1990
- Ended on
-
Monday
December 31, 1990
- Friday the 13ths
-
2
2 Friday the 13ths this year.
- Easter Sunday
-
April 15
Sunday, April 15, 1990
- Decade
-
1990s
1990–1999
- Century
-
20th century
1901–2000
- Millennium
-
2nd millennium
1001–2000
- Years ago
-
36
36 years before 2026.
- FIFA World Cup
-
Yes
Men's FIFA World Cup is held every four years (skipped 1942 and 1946 due to WWII).
In other calendars
- Hebrew
-
5750 / 5751 AM
Rosh Hashanah falls in September/October.
- Islamic Hijri
-
1410 / 1411 AH
Lunar calendar; year spans differ from Gregorian.
- Chinese
-
Year of the zodiac:Metal zodiac:Horse
Sexagenary cycle position 7 of 60. Lunar new year falls in late January / mid-February.
- Buddhist Era
-
2533 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
- Persian Solar Hijri
-
1368 / 1369 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
- Ethiopian
-
1982 / 1983 ET
Year boundary at Enkutatash (September 11/12).
- Indian National (Saka)
-
1912 / 1911 Saka
Indian national calendar; year starts in March.
- Japanese
-
Heisei 2
Reign-era counting from the start of each emperor's reign.
Properties
- Parity
- Even
- Digit count
- 4
- Digit sum
- 19
- Digit product
- 0
- Digital root
- 1
- Palindrome
- No
- Bit width
- 11 bits
- Reversed
- 991
- Flips to (rotate 180°)
- 661
- Recamán's sequence
- a(3,771) = 1,990
- Square (n²)
- 3,960,100
- Cube (n³)
- 7,880,599,000
- Divisor count
- 8
- σ(n) — sum of divisors
- 3,600
- φ(n) — Euler's totient
- 792
- Sum of prime factors
- 206
Primality
Prime factorization: 2 × 5 × 199
Divisors & multiples
Sums & aliquot sequence
Representations
- In words
- one thousand nine hundred ninety
- Ordinal
- 1990th
- Roman numeral
- MCMXC
- Binary
- 11111000110
- Octal
- 3706
- Hexadecimal
- 0x7C6
- Base64
- B8Y=
- One's complement
- 63,545 (16-bit)
Historical numeral systems
- Babylonian (base 60)
- 𒌋𒌋𒌋𒁹𒁹𒁹 𒌋
- Egyptian hieroglyphic
- 𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆
- Greek (Milesian)
- ͵αϡϟʹ
- Mayan (base 20)
- 𝋤·𝋳·𝋪
- Chinese
- 一千九百九十
- Chinese (financial)
- 壹仟玖佰玖拾
Digit at this position in famous constants
- π — Pi (π)
- Digit 1,990 = 0
- e — Euler's number (e)
- Digit 1,990 = 1
- φ — Golden ratio (φ)
- Digit 1,990 = 1
- √2 — Pythagoras's (√2)
- Digit 1,990 = 4
- ln 2 — Natural log of 2
- Digit 1,990 = 9
- γ — Euler-Mascheroni (γ)
- Digit 1,990 = 3
Also seen as
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 1990, here are decompositions:
- 3 + 1987 = 1990
- 11 + 1979 = 1990
- 17 + 1973 = 1990
- 41 + 1949 = 1990
- 59 + 1931 = 1990
- 83 + 1907 = 1990
- 89 + 1901 = 1990
- 101 + 1889 = 1990
Showing the first eight; more decompositions exist.
UTF-8 encoding: DF 86 (2 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.7.198.
- Address
- 0.0.7.198
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.7.198
Unspecified address (0.0.0.0/8) — "this network" placeholder.
The digit sequence 1990 first appears in π at position 5,250 of the decimal expansion (the 5,250ordinal-suffix:th 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.