Number

169

169 is a composite number, odd, a calendar year.

Arithmetic Number Ascending Digits Deficient Number Evil Number Flippable Pell Number Perfect Square Powerful Number Recamán's Sequence Semiprime Year

Historical context — 169 AD

Calendar year

Year 169 (CLXIX) was a common year starting on Saturday of the Julian calendar.

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Historical context — 169 BC

Calendar year

Year 169 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: Sunday
January 1, 169
Ended on: Sunday
December 31, 169
Friday the 13ths: 2
2 Friday the 13ths this year.
Decade: 160s
160–169
Century: 2nd century
101–200
Millennium: 1st millennium
1–1000
Years ago: 1,857
1857 years before 2026.

In other calendars

Hebrew: 3929 / 3930 AM
Rosh Hashanah falls in September/October.
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: 712 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Ethiopian: 161 / 162 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 91 / 90 Saka
Indian national calendar; year starts in March.

Properties

Parity: Odd
Digit count: 3
Digit sum: 16
Digit product: 54
Digital root: 7
Palindrome: No
Bit width: 8 bits
Reversed: 961
Flips to (rotate 180°): 691
Recamán's sequence: a(329) = 169
Square (n²): 28,561
Cube (n³): 4,826,809
Square root (√n): 13
Divisor count: 3
σ(n) — sum of divisors: 183
φ(n) — Euler's totient: 156
Sum of prime factors: 26

Primality

Prime factorization: 13 ²

Nearest primes: 167 (−2) · 173 (+4)

Divisors & multiples

All divisors (3)

1 · 13 · 169

Aliquot sum (sum of proper divisors): 14

Factor pairs (a × b = 169)

1 × 169

13 × 13

First multiples

169 · 338 (double) · 507 · 676 · 845 · 1,014 · 1,183 · 1,352 · 1,521 · 1,690

Sums & aliquot sequence

As a sum of two squares: 0² + 13² = 5² + 12²

As consecutive integers: 84 + 85 7 + 8 + … + 19

Aliquot sequence: 169 → 14 → 10 → 8 → 7 → 1 → 0 — terminates at zero

Representations

In words: one hundred sixty-nine
Ordinal: 169th
Roman numeral: CLXIX
Binary: 10101001
Octal: 251
Hexadecimal: 0xA9
Base64: qQ==
One's complement: 86 (8-bit)

In other bases

ternary (3) 20021

quaternary (4) 2221

quinary (5) 1134

senary (6) 441

septenary (7) 331

nonary (9) 207

undecimal (11) 144

duodecimal (12) 121

tridecimal (13) 100

tetradecimal (14) c1

pentadecimal (15) b4

Historical numeral systems

Babylonian (base 60): 𒁹𒁹 𒌋𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹
Egyptian hieroglyphic: 𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺
Greek (Milesian): ρξθʹ
Mayan (base 20): 𝋨·𝋩
Chinese: 一百六十九
Chinese (financial): 壹佰陸拾玖

In other modern scripts

Eastern Arabic ١٦٩ Devanagari १६९ Bengali ১৬৯ Tamil ௧௬௯ Thai ๑๖๙ Tibetan ༡༦༩ Khmer ១៦៩ Lao ໑໖໙ Burmese ၁၆၉

Digit at this position in famous constants

π — Pi (π): Digit 169 = 1
e — Euler's number (e): Digit 169 = 7
φ — Golden ratio (φ): Digit 169 = 5
√2 — Pythagoras's (√2): Digit 169 = 7
ln 2 — Natural log of 2: Digit 169 = 8
γ — Euler-Mascheroni (γ): Digit 169 = 2

Also seen as

Unicode codepoint

U+00A9

Other symbol (So)

UTF-8 encoding: C2 A9 (2 bytes).

Lookup U+00A9 on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#0000A9

RGB(0, 0, 169)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.169.

Address: 0.0.0.169
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.0.169

Unspecified address (0.0.0.0/8) — "this network" placeholder.