233
233 is a prime, odd, a calendar year.
233 (two hundred thirty-three) is an odd 3-digit number. It is a prime number — divisible only by 1 and itself. It is a Fibonacci number. Written other ways, in Roman numerals it is CCXXXIII and in binary, 11101001.
Interestingness
Historical context — 233 AD
Calendar year
Year 233 (CCXXXIII) was a common year starting on Tuesday of the Julian calendar.
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Historical context — 233 BC
Calendar year
Year 233 BC was a year of the pre-Julian Roman calendar.
Excerpt from Wikipedia (en) ↗ · Licensed CC BY-SA 4.0 Read the full article on Wikipedia →
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
-
Tuesday
January 1, 233
- Ended on
-
Tuesday
December 31, 233
- Friday the 13ths
-
2
2 Friday the 13ths this year.
- Decade
-
230s
230–239
- Century
-
3rd century
201–300
- Millennium
-
1st millennium
1–1000
- Years ago
-
1,793
1793 years before 2026.
In other calendars
- Hebrew
-
3993 / 3994 AM
Rosh Hashanah falls in September/October.
- Chinese
-
Year of the zodiac:Water zodiac:Ox
Sexagenary cycle position 50 of 60. Lunar new year falls in late January / mid-February.
- Buddhist Era
-
776 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
- Ethiopian
-
225 / 226 ET
Year boundary at Enkutatash (September 11/12).
- Indian National (Saka)
-
155 / 154 Saka
Indian national calendar; year starts in March.
Properties
Primality
233 is prime. It has exactly two divisors: 1 and itself.
Divisors & multiples
Sums & aliquot sequence
Continued fraction of √n
√233 = [15; (3, 1, 3, 1, 1, 1, 1, 3, 1, 3, 30)]
Period length 11 — the block in parentheses repeats forever.
Representations
- In words
- two hundred thirty-three
- Ordinal
- 233rd
- Roman numeral
- CCXXXIII
- Binary
- 11101001
- Octal
- 351
- Hexadecimal
- 0xE9
- Base64
- 6Q==
- One's complement
- 22 (8-bit)
- Scientific notation
- 2.33 × 10²
- As a duration
- 233 s = 3 minutes, 53 seconds
As an angle
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒌋𒁹𒁹𒁹
- Egyptian hieroglyphic
- 𓍢𓍢𓎆𓎆𓎆𓏺𓏺𓏺
- Greek (Milesian)
- σλγʹ
- Mayan (base 20)
- 𝋫·𝋭
- Chinese
- 二百三十三
- Chinese (financial)
- 貳佰參拾參
Digit at this position in famous constants
- π — Pi (π)
- Digit 233 = 7
- e — Euler's number (e)
- Digit 233 = 1
- φ — Golden ratio (φ)
- Digit 233 = 0
- √2 — Pythagoras's (√2)
- Digit 233 = 7
- ln 2 — Natural log of 2
- Digit 233 = 9
- γ — Euler-Mascheroni (γ)
- Digit 233 = 6
Also seen as
UTF-8 encoding: C3 A9 (2 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.233.
- Address
- 0.0.0.233
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.0.233
Unspecified address (0.0.0.0/8) — "this network" placeholder.
Heard as a frequency, 233 Hz is closest to:
- Concert pitch (A4 = 440 Hz): A♯3 (233.1 Hz, -1¢)
- Scientific pitch (C4 = 256 Hz): A♯3 (228.1 Hz, +37¢)
- Baroque pitch (A4 = 415 Hz): B3 (232.9 Hz, +1¢)
Related reading
- Prime numbers — The building blocks of arithmetic: what primes are, why they matter, and how we find them.
- Fibonacci numbers — The sequence where each term is the sum of the two before it — and why it turns up everywhere.
- Mayan numerals — Vigesimal dots-and-bars with a shell zero — one of the earliest true zeros.