Number

1,211

1,211 is a composite number, odd, a calendar year.

1,211 (one thousand two hundred eleven) is an odd 4-digit number. It is a composite number with 4 divisors, and factors as 7 × 173. Written other ways, in Roman numerals it is MCCXI and in binary, 10010111011.

Arithmetic Number Cube-Free Deficient Number Happy Number Odious Number Pernicious Number Recamán's Sequence Semiprime Squarefree Year

Interestingness

★ ★ ★ ★ ☆

6 notable facts · grade B

1,199 1,200 1,201 1,202 1,203 1,204 1,205 1,206 1,207 1,208 1,209 1,210 1,211 1,212 1,213 1,214 1,215 1,216 1,217 1,218 1,219 1,220 1,221 1,222 1,223

less more

Historical context — 1211 AD

Calendar year

Year 1211 (MCCXI) was a common year starting on Saturday of the Julian 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: Saturday
January 1, 1211
Ended on: Saturday
December 31, 1211
Friday the 13ths: 1
One Friday the 13th this year.
Decade: 1210s
1210–1219
Century: 13th century
1201–1300
Millennium: 2nd millennium
1001–2000
Years ago: 815
815 years before 2026.

In other calendars

Hebrew: 4971 / 4972 AM
Rosh Hashanah falls in September/October.
Islamic Hijri: 607 / 608 AH
Lunar calendar; year spans differ from Gregorian.
Chinese: Year of the zodiac:Metal zodiac:Goat
Sexagenary cycle position 8 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 1754 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri: 589 / 590 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian: 1203 / 1204 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 1133 / 1132 Saka
Indian national calendar; year starts in March.

Properties

Parity: Odd
Digit count: 4
Digit sum: 5
Digit product: 2
Digital root: 5
Palindrome: No
Bit width: 11 bits
Reversed: 1,121
Recamán's sequence: a(8,566) = 1,211
Square (n²): 1,466,521
Cube (n³): 1,775,956,931
Divisor count: 4
σ(n) — sum of divisors: 1,392
φ(n) — Euler's totient: 1,032
Sum of prime factors: 180

Primality

Prime factorization: 7 × 173

Nearest primes: 1,201 (−10) · 1,213 (+2)

Divisors & multiples

All divisors (4)

1 · 7 · 173 · 1211

Aliquot sum (sum of proper divisors): 181

Factor pairs (a × b = 1,211)

1 × 1211

7 × 173

First multiples

1,211 · 2,422 (double) · 3,633 · 4,844 · 6,055 · 7,266 · 8,477 · 9,688 · 10,899 · 12,110

Sums & aliquot sequence

As consecutive integers: 605 + 606 170 + 171 + … + 176 80 + 81 + … + 93

Aliquot sequence: 1,211 → 181 → 1 → 0 — terminates at zero

Continued fraction of √n

√1,211 = [34; (1, 3, 1, 68)]

Period length 4 — the block in parentheses repeats forever.

Representations

In words: one thousand two hundred eleven
Ordinal: 1211th
Roman numeral: MCCXI
Binary: 10010111011
Octal: 2273
Hexadecimal: 0x4BB
Base64: BLs=
One's complement: 64,324 (16-bit)
Scientific notation: 1.211 × 10³
As a duration: 1,211 s = 20 minutes, 11 seconds

In other bases

ternary (3) 1122212

quaternary (4) 102323

quinary (5) 14321

senary (6) 5335

septenary (7) 3350

nonary (9) 1585

undecimal (11) a01

duodecimal (12) 84b

tridecimal (13) 722

tetradecimal (14) 627

pentadecimal (15) 55b

Palindromic in base 6

As an angle

1,211° = 3 × 360° + 131°

131° ≈ 2.286 rad

Compass bearing: SE (southeast)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒌋𒌋 𒌋𒁹
Egyptian hieroglyphic: 𓆼𓍢𓍢𓎆𓏺
Greek (Milesian): ͵ασιαʹ
Mayan (base 20): 𝋣·𝋠·𝋫
Chinese: 一千二百一十一
Chinese (financial): 壹仟貳佰壹拾壹

In other modern scripts

Eastern Arabic ١٢١١ Devanagari १२११ Bengali ১২১১ Tamil ௧௨௧௧ Thai ๑๒๑๑ Tibetan ༡༢༡༡ Khmer ១២១១ Lao ໑໒໑໑ Burmese ၁၂၁၁

Digit at this position in famous constants

π — Pi (π): Digit 1,211 = 5
e — Euler's number (e): Digit 1,211 = 9
φ — Golden ratio (φ): Digit 1,211 = 3
√2 — Pythagoras's (√2): Digit 1,211 = 4
ln 2 — Natural log of 2: Digit 1,211 = 2
γ — Euler-Mascheroni (γ): Digit 1,211 = 2

Also seen as

Unicode codepoint

Cyrillic Small Letter Shha

U+04BB

Lowercase letter (Ll)

UTF-8 encoding: D2 BB (2 bytes).

Lookup U+04BB on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#0004BB

RGB(0, 4, 187)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.4.187.

Address: 0.0.4.187
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.4.187

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

Musical pitch

Heard as a frequency, 1,211 Hz is closest to:

Concert pitch (A4 = 440 Hz): D♯6 (1244.5 Hz, -47¢ — about midway to D6)
Scientific pitch (C4 = 256 Hz): D♯6 (1217.7 Hz, -10¢)
Baroque pitch (A4 = 415 Hz): E6 (1243.6 Hz, -46¢ — about midway to D♯6)

Position in π

The digit sequence 1211 first appears in π at position 50,288 of the decimal expansion (the 50,288ordinal-suffix:th digit after the integer 3).

Search range: the first 1,000,000 fractional digits of π. Any 6-digit-or-shorter string is virtually guaranteed to appear in there — the more interesting signal is the position.

Look up 1211 on Pi Search ↗