1,688
1,688 is a composite number, even, a calendar year.
Notable events — 1688 AD
- Nov 5 William of Orange lands at Torbay, beginning the Glorious Revolution.
- Dec 11 James II flees England.
- Sep 24 Louis XIV invades the Palatinate, starting the Nine Years' War.
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
-
53
Long year: contains 53 ISO weeks.
- Started on
-
Thursday
January 1, 1688
- Ended on
-
Friday
December 31, 1688
- Friday the 13ths
-
2
2 Friday the 13ths this year.
- Easter Sunday
-
April 18
Sunday, April 18, 1688
- Decade
-
1680s
1680–1689
- Century
-
17th century
1601–1700
- Millennium
-
2nd millennium
1001–2000
- Years ago
-
338
338 years before 2026.
In other calendars
- Hebrew
-
5448 / 5449 AM
Rosh Hashanah falls in September/October.
- Islamic Hijri
-
1099 / 1100 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
-
2231 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
- Persian Solar Hijri
-
1066 / 1067 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
- Ethiopian
-
1680 / 1681 ET
Year boundary at Enkutatash (September 11/12).
- Indian National (Saka)
-
1610 / 1609 Saka
Indian national calendar; year starts in March.
Properties
- Parity
- Even
- Digit count
- 4
- Digit sum
- 23
- Digit product
- 384
- Digital root
- 5
- Palindrome
- No
- Bit width
- 11 bits
- Reversed
- 8,861
- Flips to (rotate 180°)
- 8,891
- Recamán's sequence
- a(844) = 1,688
- Square (n²)
- 2,849,344
- Cube (n³)
- 4,809,692,672
- Divisor count
- 8
- σ(n) — sum of divisors
- 3,180
- φ(n) — Euler's totient
- 840
- Sum of prime factors
- 217
Primality
Prime factorization: 2 3 × 211
Divisors & multiples
Sums & aliquot sequence
Representations
- In words
- one thousand six hundred eighty-eight
- Ordinal
- 1688th
- Roman numeral
- MDCLXXXVIII
- Binary
- 11010011000
- Octal
- 3230
- Hexadecimal
- 0x698
- Base64
- Bpg=
- One's complement
- 63,847 (16-bit)
Historical numeral systems
- Babylonian (base 60)
- 𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹 𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹
- Egyptian hieroglyphic
- 𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺
- Greek (Milesian)
- ͵αχπηʹ
- Mayan (base 20)
- 𝋤·𝋤·𝋨
- Chinese
- 一千六百八十八
- Chinese (financial)
- 壹仟陸佰捌拾捌
Digit at this position in famous constants
- π — Pi (π)
- Digit 1,688 = 3
- e — Euler's number (e)
- Digit 1,688 = 2
- φ — Golden ratio (φ)
- Digit 1,688 = 9
- √2 — Pythagoras's (√2)
- Digit 1,688 = 5
- ln 2 — Natural log of 2
- Digit 1,688 = 7
- γ — Euler-Mascheroni (γ)
- Digit 1,688 = 0
Also seen as
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 1688, here are decompositions:
- 19 + 1669 = 1688
- 31 + 1657 = 1688
- 61 + 1627 = 1688
- 67 + 1621 = 1688
- 79 + 1609 = 1688
- 109 + 1579 = 1688
- 139 + 1549 = 1688
- 157 + 1531 = 1688
Showing the first eight; more decompositions exist.
UTF-8 encoding: DA 98 (2 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.6.152.
- Address
- 0.0.6.152
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.6.152
Unspecified address (0.0.0.0/8) — "this network" placeholder.
The digit sequence 1688 first appears in π at position 5,152 of the decimal expansion (the 5,152ordinal-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.