1,209
1,209 is a composite number, odd, a calendar year.
Historical context — 1209 AD
Calendar year
Year 1209 (MCCIX) was a common year starting on Thursday of the Julian calendar.
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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
-
53
Long year: contains 53 ISO weeks.
- Started on
-
Thursday
January 1, 1209
- Ended on
-
Thursday
December 31, 1209
- Friday the 13ths
-
3
3 Friday the 13ths this year.
- Decade
-
1200s
1200–1209
- Century
-
13th century
1201–1300
- Millennium
-
2nd millennium
1001–2000
- Years ago
-
817
817 years before 2026.
In other calendars
- Hebrew
-
4969 / 4970 AM
Rosh Hashanah falls in September/October.
- Islamic Hijri
-
605 / 606 AH
Lunar calendar; year spans differ from Gregorian.
- Chinese
-
Year of the zodiac:Earth zodiac:Snake
Sexagenary cycle position 6 of 60. Lunar new year falls in late January / mid-February.
- Buddhist Era
-
1752 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
- Persian Solar Hijri
-
587 / 588 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
- Ethiopian
-
1201 / 1202 ET
Year boundary at Enkutatash (September 11/12).
- Indian National (Saka)
-
1131 / 1130 Saka
Indian national calendar; year starts in March.
Properties
Primality
Prime factorization: 3 × 13 × 31
Divisors & multiples
Sums & aliquot sequence
Representations
- In words
- one thousand two hundred nine
- Ordinal
- 1209th
- Roman numeral
- MCCIX
- Binary
- 10010111001
- Octal
- 2271
- Hexadecimal
- 0x4B9
- Base64
- BLk=
- One's complement
- 64,326 (16-bit)
Historical numeral systems
- Babylonian (base 60)
- 𒌋𒌋 𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹
- Egyptian hieroglyphic
- 𓆼𓍢𓍢𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺
- Greek (Milesian)
- ͵ασθʹ
- Mayan (base 20)
- 𝋣·𝋠·𝋩
- Chinese
- 一千二百零九
- Chinese (financial)
- 壹仟貳佰零玖
Digit at this position in famous constants
- π — Pi (π)
- Digit 1,209 = 0
- e — Euler's number (e)
- Digit 1,209 = 5
- φ — Golden ratio (φ)
- Digit 1,209 = 7
- √2 — Pythagoras's (√2)
- Digit 1,209 = 9
- ln 2 — Natural log of 2
- Digit 1,209 = 2
- γ — Euler-Mascheroni (γ)
- Digit 1,209 = 4
Also seen as
UTF-8 encoding: D2 B9 (2 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.4.185.
- Address
- 0.0.4.185
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.4.185
Unspecified address (0.0.0.0/8) — "this network" placeholder.
The digit sequence 1209 first appears in π at position 4,728 of the decimal expansion (the 4,728ordinal-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.