Number

321

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

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

Historical context — 321 AD

Calendar year

Year 321 (CCCXXI) was a common year starting on Sunday of the Julian calendar.

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Historical context — 321 BC

Calendar year

Year 321 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: Saturday
January 1, 321
Ended on: Saturday
December 31, 321
Friday the 13ths: 1
One Friday the 13th this year.
Decade: 320s
320–329
Century: 4th century
301–400
Millennium: 1st millennium
1–1000
Years ago: 1,705
1705 years before 2026.

In other calendars

Hebrew: 4081 / 4082 AM
Rosh Hashanah falls in September/October.
Chinese: Year of the zodiac:Metal zodiac:Snake
Sexagenary cycle position 18 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 864 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Ethiopian: 313 / 314 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 243 / 242 Saka
Indian national calendar; year starts in March.

Properties

Parity: Odd
Digit count: 3
Digit sum: 6
Digit product: 6
Digital root: 6
Palindrome: No
Bit width: 9 bits
Reversed: 123
Recamán's sequence: a(606) = 321
Square (n²): 103,041
Cube (n³): 33,076,161
Divisor count: 4
σ(n) — sum of divisors: 432
φ(n) — Euler's totient: 212
Sum of prime factors: 110

Primality

Prime factorization: 3 × 107

Nearest primes: 317 (−4) · 331 (+10)

Divisors & multiples

All divisors (4)

1 · 3 · 107 · 321

Aliquot sum (sum of proper divisors): 111

Factor pairs (a × b = 321)

1 × 321

3 × 107

First multiples

321 · 642 (double) · 963 · 1,284 · 1,605 · 1,926 · 2,247 · 2,568 · 2,889 · 3,210

Sums & aliquot sequence

As consecutive integers: 160 + 161 106 + 107 + 108 51 + 52 + 53 + 54 + 55 + 56

Aliquot sequence: 321 → 111 → 41 → 1 → 0 — terminates at zero

Representations

In words: three hundred twenty-one
Ordinal: 321st
Roman numeral: CCCXXI
Binary: 101000001
Octal: 501
Hexadecimal: 0x141
Base64: AUE=
One's complement: 65,214 (16-bit)

In other bases

ternary (3) 102220

quaternary (4) 11001

quinary (5) 2241

senary (6) 1253

septenary (7) 636

nonary (9) 386

undecimal (11) 272

duodecimal (12) 229

tridecimal (13) 1b9

tetradecimal (14) 18d

pentadecimal (15) 166

Historical numeral systems

Babylonian (base 60): 𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒁹
Egyptian hieroglyphic: 𓍢𓍢𓍢𓎆𓎆𓏺
Greek (Milesian): τκαʹ
Mayan (base 20): 𝋰·𝋡
Chinese: 三百二十一
Chinese (financial): 參佰貳拾壹

In other modern scripts

Eastern Arabic ٣٢١ Devanagari ३२१ Bengali ৩২১ Tamil ௩௨௧ Thai ๓๒๑ Tibetan ༣༢༡ Khmer ៣២១ Lao ໓໒໑ Burmese ၃၂၁

Digit at this position in famous constants

π — Pi (π): Digit 321 = 7
e — Euler's number (e): Digit 321 = 3
φ — Golden ratio (φ): Digit 321 = 4
√2 — Pythagoras's (√2): Digit 321 = 2
ln 2 — Natural log of 2: Digit 321 = 4
γ — Euler-Mascheroni (γ): Digit 321 = 5

Also seen as

Unicode codepoint

Latin Capital Letter L With Stroke

U+0141

Uppercase letter (Lu)

UTF-8 encoding: C5 81 (2 bytes).

Lookup U+0141 on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#000141

RGB(0, 1, 65)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.1.65.

Address: 0.0.1.65
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.1.65

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

NANP area code 321

The number 321 is an active NANP area code (North American Numbering Plan).

Primary area: Orlando / Space Coast
Region: Florida
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 321 ↗