1,684
1,684 is a composite number, even, a calendar year.
Notable events — 1684 AD
- Mar 5 The Holy League against the Ottomans is formed.
- Aug 18 The Treaty of Ratisbon halts the Reunions War.
- Jun 21 Massachusetts Bay's charter is annulled.
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
-
Saturday
January 1, 1684
- Ended on
-
Sunday
December 31, 1684
- Friday the 13ths
-
1
One Friday the 13th this year.
- Easter Sunday
-
April 2
Sunday, April 2, 1684
- Decade
-
1680s
1680–1689
- Century
-
17th century
1601–1700
- Millennium
-
2nd millennium
1001–2000
- Years ago
-
342
342 years before 2026.
In other calendars
- Hebrew
-
5444 / 5445 AM
Rosh Hashanah falls in September/October.
- Islamic Hijri
-
1095 / 1096 AH
Lunar calendar; year spans differ from Gregorian.
- Chinese
-
Year of the zodiac:Wood zodiac:Rat
Sexagenary cycle position 1 of 60. Lunar new year falls in late January / mid-February.
- Buddhist Era
-
2227 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
- Persian Solar Hijri
-
1062 / 1063 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
- Ethiopian
-
1676 / 1677 ET
Year boundary at Enkutatash (September 11/12).
- Indian National (Saka)
-
1606 / 1605 Saka
Indian national calendar; year starts in March.
Properties
Primality
Prime factorization: 2 2 × 421
Divisors & multiples
Sums & aliquot sequence
Representations
- In words
- one thousand six hundred eighty-four
- Ordinal
- 1684th
- Roman numeral
- MDCLXXXIV
- Binary
- 11010010100
- Octal
- 3224
- Hexadecimal
- 0x694
- Base64
- BpQ=
- One's complement
- 63,851 (16-bit)
Historical numeral systems
- Babylonian (base 60)
- 𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹 𒁹𒁹𒁹𒁹
- Egyptian hieroglyphic
- 𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺𓏺𓏺𓏺
- Greek (Milesian)
- ͵αχπδʹ
- Mayan (base 20)
- 𝋤·𝋤·𝋤
- Chinese
- 一千六百八十四
- Chinese (financial)
- 壹仟陸佰捌拾肆
Digit at this position in famous constants
- π — Pi (π)
- Digit 1,684 = 8
- e — Euler's number (e)
- Digit 1,684 = 6
- φ — Golden ratio (φ)
- Digit 1,684 = 9
- √2 — Pythagoras's (√2)
- Digit 1,684 = 9
- ln 2 — Natural log of 2
- Digit 1,684 = 6
- γ — Euler-Mascheroni (γ)
- Digit 1,684 = 3
Also seen as
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 1684, here are decompositions:
- 17 + 1667 = 1684
- 47 + 1637 = 1684
- 71 + 1613 = 1684
- 83 + 1601 = 1684
- 101 + 1583 = 1684
- 113 + 1571 = 1684
- 131 + 1553 = 1684
- 173 + 1511 = 1684
Showing the first eight; more decompositions exist.
UTF-8 encoding: DA 94 (2 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.6.148.
- Address
- 0.0.6.148
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.6.148
Unspecified address (0.0.0.0/8) — "this network" placeholder.
The digit sequence 1684 first appears in π at position 2,402 of the decimal expansion (the 2,402ordinal-suffix:nd 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.