198
198 is a composite number, even, a calendar year.
Historical context — 198 AD
Calendar year
Year 198 (CXCVIII) was a common year starting on Sunday of the Julian calendar.
Excerpt from Wikipedia (en) ↗ · Licensed CC BY-SA 4.0 · English fallback Read the full article on Wikipedia →
Historical context — 198 BC
Calendar year
Year 198 BC was a year of the pre-Julian Roman calendar.
Excerpt from Wikipedia (en) ↗ · Licensed CC BY-SA 4.0 · English fallback 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
-
Monday
January 1, 198
- Ended on
-
Monday
December 31, 198
- Friday the 13ths
-
2
2 Friday the 13ths this year.
- Decade
-
190s
190–199
- Century
-
2nd century
101–200
- Millennium
-
1st millennium
1–1000
- Years ago
-
1,828
1828 years before 2026.
In other calendars
- Hebrew
-
3958 / 3959 AM
Rosh Hashanah falls in September/October.
- Chinese
-
Year of the zodiac:Earth zodiac:Tiger
Sexagenary cycle position 15 of 60. Lunar new year falls in late January / mid-February.
- Buddhist Era
-
741 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
- Ethiopian
-
190 / 191 ET
Year boundary at Enkutatash (September 11/12).
- Indian National (Saka)
-
120 / 119 Saka
Indian national calendar; year starts in March.
Properties
- Parity
- Even
- Digit count
- 3
- Digit sum
- 18
- Digit product
- 72
- Digital root
- 9
- Palindrome
- No
- Bit width
- 8 bits
- Reversed
- 891
- Flips to (rotate 180°)
- 861
- Recamán's sequence
- a(1,375) = 198
- Square (n²)
- 39,204
- Cube (n³)
- 7,762,392
- Divisor count
- 12
- σ(n) — sum of divisors
- 468
- φ(n) — Euler's totient
- 60
- Sum of prime factors
- 19
Primality
Prime factorization: 2 × 3 2 × 11
Divisors & multiples
Sums & aliquot sequence
Representations
- In words
- one hundred ninety-eight
- Ordinal
- 198th
- Roman numeral
- CXCVIII
- Binary
- 11000110
- Octal
- 306
- Hexadecimal
- 0xC6
- Base64
- xg==
- One's complement
- 57 (8-bit)
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹 𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹
- Egyptian hieroglyphic
- 𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺
- Greek (Milesian)
- ρϟηʹ
- Mayan (base 20)
- 𝋩·𝋲
- Chinese
- 一百九十八
- Chinese (financial)
- 壹佰玖拾捌
Digit at this position in famous constants
- π — Pi (π)
- Digit 198 = 8
- e — Euler's number (e)
- Digit 198 = 1
- φ — Golden ratio (φ)
- Digit 198 = 6
- √2 — Pythagoras's (√2)
- Digit 198 = 7
- ln 2 — Natural log of 2
- Digit 198 = 2
- γ — Euler-Mascheroni (γ)
- Digit 198 = 9
Also seen as
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 198, here are decompositions:
- 5 + 193 = 198
- 7 + 191 = 198
- 17 + 181 = 198
- 19 + 179 = 198
- 31 + 167 = 198
- 41 + 157 = 198
- 47 + 151 = 198
- 59 + 139 = 198
Showing the first eight; more decompositions exist.
UTF-8 encoding: C3 86 (2 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.198.
- Address
- 0.0.0.198
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.0.198
Unspecified address (0.0.0.0/8) — "this network" placeholder.