1,609
1,609 is a prime, odd, a calendar year.
1,609 (one thousand six hundred nine) is an odd 4-digit number. It is a prime number — divisible only by 1 and itself. Written other ways, in Roman numerals it is MDCIX and in binary, 11001001001.
Interestingness
Notable events — 1609 AD
- Sep 12 Henry Hudson enters New York harbor and sails up the river bearing his name.
- Mar 22 Galileo Galilei begins observing the heavens with a telescope.
- Apr 9 Spain and the Dutch agree to a Twelve Years' Truce.
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
-
53
Long year: contains 53 ISO weeks.
- Started on
-
Thursday
January 1, 1609
- Ended on
-
Thursday
December 31, 1609
- Friday the 13ths
-
3
3 Friday the 13ths this year.
- Easter Sunday
-
April 19
Sunday, April 19, 1609
- Decade
-
1600s
1600–1609
- Century
-
17th century
1601–1700
- Millennium
-
2nd millennium
1001–2000
- Years ago
-
417
417 years before 2026.
In other calendars
- Hebrew
-
5369 / 5370 AM
Rosh Hashanah falls in September/October.
- Islamic Hijri
-
1017 / 1018 AH
Lunar calendar; year spans differ from Gregorian.
- Chinese
-
Year of the zodiac:Earth zodiac:Rooster
Sexagenary cycle position 46 of 60. Lunar new year falls in late January / mid-February.
- Buddhist Era
-
2152 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
- Persian Solar Hijri
-
987 / 988 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
- Ethiopian
-
1601 / 1602 ET
Year boundary at Enkutatash (September 11/12).
- Indian National (Saka)
-
1531 / 1530 Saka
Indian national calendar; year starts in March.
Properties
Primality
1,609 is prime. It has exactly two divisors: 1 and itself.
Divisors & multiples
Sums & aliquot sequence
Continued fraction of √n
√1,609 = [40; (8, 1, 9, 7, 5, 4, 1, 4, 1, 1, 5, 1, 1, 1, 1, 1, 15, 2, 2, 1, 2, 1, 1, 1, …)]
Period length 57 — the block in parentheses repeats forever.
Representations
- In words
- one thousand six hundred nine
- Ordinal
- 1609th
- Roman numeral
- MDCIX
- Binary
- 11001001001
- Octal
- 3111
- Hexadecimal
- 0x649
- Base64
- Bkk=
- One's complement
- 63,926 (16-bit)
- Scientific notation
- 1.609 × 10³
- As a duration
- 1,609 s = 26 minutes, 49 seconds
As an angle
Historical numeral systems
- Babylonian (base 60)
- 𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹
- Egyptian hieroglyphic
- 𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺
- Greek (Milesian)
- ͵αχθʹ
- Mayan (base 20)
- 𝋤·𝋠·𝋩
- Chinese
- 一千六百零九
- Chinese (financial)
- 壹仟陸佰零玖
Digit at this position in famous constants
- π — Pi (π)
- Digit 1,609 = 0
- e — Euler's number (e)
- Digit 1,609 = 0
- φ — Golden ratio (φ)
- Digit 1,609 = 6
- √2 — Pythagoras's (√2)
- Digit 1,609 = 9
- ln 2 — Natural log of 2
- Digit 1,609 = 5
- γ — Euler-Mascheroni (γ)
- Digit 1,609 = 4
Also seen as
UTF-8 encoding: D9 89 (2 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.6.73.
- Address
- 0.0.6.73
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.6.73
Unspecified address (0.0.0.0/8) — "this network" placeholder.
Heard as a frequency, 1,609 Hz is closest to:
- Concert pitch (A4 = 440 Hz): G6 (1568 Hz, +45¢ — about midway to G♯6)
- Scientific pitch (C4 = 256 Hz): G♯6 (1625.5 Hz, -18¢)
- Baroque pitch (A4 = 415 Hz): G♯6 (1566.8 Hz, +46¢ — about midway to A6)
1,609 is the number of metres in a mile (1,609.344 m, rounded down).
The digit sequence 1609 first appears in π at position 396 of the decimal expansion (the 396ordinal-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.
Related reading
- Prime numbers — The building blocks of arithmetic: what primes are, why they matter, and how we find them.
- Egyptian hieroglyphic numerals — Seven hieroglyphs for every power of ten, from a single stroke to a million.