Number

445

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

Arithmetic Number Deficient Number Odious Number Pernicious Number Recamán's Sequence Semiprime Squarefree Year

Historical context — 445 AD

Calendar year

Year 445 (CDXLV) was a common year starting on Monday of the Julian calendar.

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Historical context — 445 BC

Calendar year

Year 445 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, 445
Ended on: Sunday
December 31, 445
Friday the 13ths: 2
2 Friday the 13ths this year.
Decade: 440s
440–449
Century: 5th century
401–500
Millennium: 1st millennium
1–1000
Years ago: 1,581
1581 years before 2026.

In other calendars

Hebrew: 4205 / 4206 AM
Rosh Hashanah falls in September/October.
Chinese: Year of the zodiac:Wood zodiac:Rooster
Sexagenary cycle position 22 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 988 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Ethiopian: 437 / 438 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 367 / 366 Saka
Indian national calendar; year starts in March.

Properties

Parity: Odd
Digit count: 3
Digit sum: 13
Digit product: 80
Digital root: 4
Palindrome: No
Bit width: 9 bits
Reversed: 544
Recamán's sequence: a(4,753) = 445
Square (n²): 198,025
Cube (n³): 88,121,125
Divisor count: 4
σ(n) — sum of divisors: 540
φ(n) — Euler's totient: 352
Sum of prime factors: 94

Primality

Prime factorization: 5 × 89

Nearest primes: 443 (−2) · 449 (+4)

Divisors & multiples

All divisors (4)

1 · 5 · 89 · 445

Aliquot sum (sum of proper divisors): 95

Factor pairs (a × b = 445)

1 × 445

5 × 89

First multiples

445 · 890 (double) · 1,335 · 1,780 · 2,225 · 2,670 · 3,115 · 3,560 · 4,005 · 4,450

Sums & aliquot sequence

As a sum of two squares: 2² + 21² = 11² + 18²

As consecutive integers: 222 + 223 87 + 88 + 89 + 90 + 91 40 + 41 + … + 49

Aliquot sequence: 445 → 95 → 25 → 6 → 6 — reaches a perfect number

Representations

In words: four hundred forty-five
Ordinal: 445th
Roman numeral: CDXLV
Binary: 110111101
Octal: 675
Hexadecimal: 0x1BD
Base64: Ab0=
One's complement: 65,090 (16-bit)

In other bases

ternary (3) 121111

quaternary (4) 12331

quinary (5) 3240

senary (6) 2021

septenary (7) 1204

nonary (9) 544

undecimal (11) 375

duodecimal (12) 311

tridecimal (13) 283

tetradecimal (14) 23b

pentadecimal (15) 1ea

Historical numeral systems

Babylonian (base 60): 𒁹𒁹𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒁹𒁹𒁹𒁹𒁹
Egyptian hieroglyphic: 𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓏺𓏺𓏺𓏺𓏺
Greek (Milesian): υμεʹ
Mayan (base 20): 𝋡·𝋢·𝋥
Chinese: 四百四十五
Chinese (financial): 肆佰肆拾伍

In other modern scripts

Eastern Arabic ٤٤٥ Devanagari ४४५ Bengali ৪৪৫ Tamil ௪௪௫ Thai ๔๔๕ Tibetan ༤༤༥ Khmer ៤៤៥ Lao ໔໔໕ Burmese ၄၄၅

Digit at this position in famous constants

π — Pi (π): Digit 445 = 5
e — Euler's number (e): Digit 445 = 6
φ — Golden ratio (φ): Digit 445 = 7
√2 — Pythagoras's (√2): Digit 445 = 3
ln 2 — Natural log of 2: Digit 445 = 8
γ — Euler-Mascheroni (γ): Digit 445 = 9

Also seen as

Unicode codepoint

Latin Small Letter Tone Five

U+01BD

Lowercase letter (Ll)

UTF-8 encoding: C6 BD (2 bytes).

Lookup U+01BD on Compart ↗ Lookup on FileFormat.Info ↗

Network port

TCP/UDP port 445 is the well-known port for SMB — Server Message Block — Windows file sharing.

Hex color

#0001BD

RGB(0, 1, 189)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.1.189.

Address: 0.0.1.189
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.1.189

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

NANP area code 445

The number 445 is an active NANP area code (North American Numbering Plan).

Primary area: Philadelphia
Region: Pennsylvania
Country: United States

Most NANP area codes have multiple overlays in dense regions; the primary area listed is the historic/largest population center for this code.

Look up area code 445 ↗