1,808
1,808 is a composite number, even, a calendar year.
Notable events — 1808 AD
- Jan 1 The US ban on importing slaves takes effect.
- May 2 Spaniards rise against French occupation; "the Second of May" is depicted by Goya.
- Jun 6 Joseph Bonaparte becomes king of Spain.
- Sep 27 The Congress of Erfurt reaffirms the Tilsit alliance.
- Dec 22 Beethoven premieres his Fifth and Sixth Symphonies in Vienna.
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
-
Friday
January 1, 1808
- Ended on
-
Saturday
December 31, 1808
- Friday the 13ths
-
1
One Friday the 13th this year.
- Easter Sunday
-
April 17
Sunday, April 17, 1808
- Decade
-
1800s
1800–1809
- Century
-
19th century
1801–1900
- Millennium
-
2nd millennium
1001–2000
- Years ago
-
218
218 years before 2026.
- US presidential election
-
Yes
US holds a presidential election in years divisible by 4 starting from 1788.
In other calendars
- Hebrew
-
5568 / 5569 AM
Rosh Hashanah falls in September/October.
- Islamic Hijri
-
1222 / 1223 AH
Lunar calendar; year spans differ from Gregorian.
- Chinese
-
Year of the zodiac:Earth zodiac:Dragon
Sexagenary cycle position 5 of 60. Lunar new year falls in late January / mid-February.
- Buddhist Era
-
2351 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
- Persian Solar Hijri
-
1186 / 1187 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
- Ethiopian
-
1800 / 1801 ET
Year boundary at Enkutatash (September 11/12).
- Indian National (Saka)
-
1730 / 1729 Saka
Indian national calendar; year starts in March.
Properties
- Parity
- Even
- Digit count
- 4
- Digit sum
- 17
- Digit product
- 0
- Digital root
- 8
- Palindrome
- No
- Bit width
- 11 bits
- Reversed
- 8,081
- Flips to (rotate 180°)
- 8,081
- Recamán's sequence
- a(16,083) = 1,808
- Square (n²)
- 3,268,864
- Cube (n³)
- 5,910,106,112
- Divisor count
- 10
- σ(n) — sum of divisors
- 3,534
- φ(n) — Euler's totient
- 896
- Sum of prime factors
- 121
Primality
Prime factorization: 2 4 × 113
Divisors & multiples
Sums & aliquot sequence
Representations
- In words
- one thousand eight hundred eight
- Ordinal
- 1808th
- Roman numeral
- MDCCCVIII
- Binary
- 11100010000
- Octal
- 3420
- Hexadecimal
- 0x710
- Base64
- BxA=
- One's complement
- 63,727 (16-bit)
Historical numeral systems
- Babylonian (base 60)
- 𒌋𒌋𒌋 𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹
- Egyptian hieroglyphic
- 𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺
- Greek (Milesian)
- ͵αωηʹ
- Mayan (base 20)
- 𝋤·𝋪·𝋨
- Chinese
- 一千八百零八
- Chinese (financial)
- 壹仟捌佰零捌
Digit at this position in famous constants
- π — Pi (π)
- Digit 1,808 = 9
- e — Euler's number (e)
- Digit 1,808 = 1
- φ — Golden ratio (φ)
- Digit 1,808 = 7
- √2 — Pythagoras's (√2)
- Digit 1,808 = 7
- ln 2 — Natural log of 2
- Digit 1,808 = 2
- γ — Euler-Mascheroni (γ)
- Digit 1,808 = 1
Also seen as
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 1808, here are decompositions:
- 7 + 1801 = 1808
- 19 + 1789 = 1808
- 31 + 1777 = 1808
- 61 + 1747 = 1808
- 67 + 1741 = 1808
- 109 + 1699 = 1808
- 139 + 1669 = 1808
- 151 + 1657 = 1808
Showing the first eight; more decompositions exist.
UTF-8 encoding: DC 90 (2 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.7.16.
- Address
- 0.0.7.16
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.7.16
Unspecified address (0.0.0.0/8) — "this network" placeholder.
The digit sequence 1808 first appears in π at position 26,034 of the decimal expansion (the 26,034ordinal-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.