1,631
1,631 is a composite number, odd, a calendar year.
Notable events — 1631 AD
- May 20 Imperial troops sack Magdeburg; up to 25,000 are killed.
- Sep 17 Gustavus Adolphus crushes the Catholic League at Breitenfeld.
- Dec 16 Mount Vesuvius erupts violently.
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
-
Wednesday
January 1, 1631
- Ended on
-
Wednesday
December 31, 1631
- Friday the 13ths
-
1
One Friday the 13th this year.
- Easter Sunday
-
April 20
Sunday, April 20, 1631
- Decade
-
1630s
1630–1639
- Century
-
17th century
1601–1700
- Millennium
-
2nd millennium
1001–2000
- Years ago
-
395
395 years before 2026.
In other calendars
- Hebrew
-
5391 / 5392 AM
Rosh Hashanah falls in September/October.
- Islamic Hijri
-
1040 / 1041 AH
Lunar calendar; year spans differ from Gregorian.
- Chinese
-
Year of the zodiac:Metal zodiac:Goat
Sexagenary cycle position 8 of 60. Lunar new year falls in late January / mid-February.
- Buddhist Era
-
2174 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
- Persian Solar Hijri
-
1009 / 1010 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
- Ethiopian
-
1623 / 1624 ET
Year boundary at Enkutatash (September 11/12).
- Indian National (Saka)
-
1553 / 1552 Saka
Indian national calendar; year starts in March.
Properties
Primality
Prime factorization: 7 × 233
Divisors & multiples
Sums & aliquot sequence
Representations
- In words
- one thousand six hundred thirty-one
- Ordinal
- 1631st
- Roman numeral
- MDCXXXI
- Binary
- 11001011111
- Octal
- 3137
- Hexadecimal
- 0x65F
- Base64
- Bl8=
- One's complement
- 63,904 (16-bit)
Historical numeral systems
- Babylonian (base 60)
- 𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹 𒌋𒁹
- Egyptian hieroglyphic
- 𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓏺
- Greek (Milesian)
- ͵αχλαʹ
- Mayan (base 20)
- 𝋤·𝋡·𝋫
- Chinese
- 一千六百三十一
- Chinese (financial)
- 壹仟陸佰參拾壹
Digit at this position in famous constants
- π — Pi (π)
- Digit 1,631 = 7
- e — Euler's number (e)
- Digit 1,631 = 4
- φ — Golden ratio (φ)
- Digit 1,631 = 3
- √2 — Pythagoras's (√2)
- Digit 1,631 = 9
- ln 2 — Natural log of 2
- Digit 1,631 = 4
- γ — Euler-Mascheroni (γ)
- Digit 1,631 = 3
Also seen as
UTF-8 encoding: D9 9F (2 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.6.95.
- Address
- 0.0.6.95
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.6.95
Unspecified address (0.0.0.0/8) — "this network" placeholder.
The digit sequence 1631 first appears in π at position 5,020 of the decimal expansion (the 5,020ordinal-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.