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Number

1,215

1,215 is a composite number, odd, a calendar year.

Arithmetic Number Deficient Number Evil Number Gapful Number Happy Number Harshad / Niven Recamán's Sequence Year

Notable events — 1215 AD

  1. Jun 15 King John seals Magna Carta at Runnymede.

Events compiled from Wikipedia ↗ · Licensed CC BY-SA 4.0

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
53
Long year: contains 53 ISO weeks.
Started on
Thursday
January 1, 1215
Ended on
Thursday
December 31, 1215
Friday the 13ths
3
3 Friday the 13ths this year.
Decade
1210s
1210–1219
Century
13th century
1201–1300
Millennium
2nd millennium
1001–2000
Years ago
811
811 years before 2026.

In other calendars

Hebrew
4975 / 4976 AM
Rosh Hashanah falls in September/October.
Islamic Hijri
611 / 612 AH
Lunar calendar; year spans differ from Gregorian.
Chinese
Year of the zodiac:Wood zodiac:Pig
Sexagenary cycle position 12 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era
1758 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri
593 / 594 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian
1207 / 1208 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka)
1137 / 1136 Saka
Indian national calendar; year starts in March.

Properties

Parity
Odd
Digit count
4
Digit sum
9
Digit product
10
Digital root
9
Palindrome
No
Bit width
11 bits
Reversed
5,121
Recamán's sequence
a(8,558) = 1,215
Square (n²)
1,476,225
Cube (n³)
1,793,613,375
Divisor count
12
σ(n) — sum of divisors
2,184
φ(n) — Euler's totient
648
Sum of prime factors
20

Primality

Prime factorization: 3 5 × 5

Nearest primes: 1,213 (−2) · 1,217 (+2)

Divisors & multiples

All divisors (12)
1 · 3 · 5 · 9 · 15 · 27 · 45 · 81 · 135 · 243 · 405 · 1215
Aliquot sum (sum of proper divisors): 969
Factor pairs (a × b = 1,215)
1 × 1215
3 × 405
5 × 243
9 × 135
15 × 81
27 × 45
First multiples
1,215 · 2,430 (double) · 3,645 · 4,860 · 6,075 · 7,290 · 8,505 · 9,720 · 10,935 · 12,150

Sums & aliquot sequence

As consecutive integers: 607 + 608 404 + 405 + 406 241 + 242 + 243 + 244 + 245 200 + 201 + 202 + 203 + 204 + 205
Aliquot sequence: 1,215 969 471 161 31 1 0 — terminates at zero

Representations

In words
one thousand two hundred fifteen
Ordinal
1215th
Roman numeral
MCCXV
Binary
10010111111
Octal
2277
Hexadecimal
0x4BF
Base64
BL8=
One's complement
64,320 (16-bit)
In other bases
ternary (3) 1200000
quaternary (4) 102333
quinary (5) 14330
senary (6) 5343
septenary (7) 3354
nonary (9) 1600
undecimal (11) a05
duodecimal (12) 853
tridecimal (13) 726
tetradecimal (14) 62b
pentadecimal (15) 560

Historical numeral systems

Babylonian (base 60)
𒌋𒌋 𒌋𒁹𒁹𒁹𒁹𒁹
Egyptian hieroglyphic
𓆼𓍢𓍢𓎆𓏺𓏺𓏺𓏺𓏺
Greek (Milesian)
͵ασιεʹ
Mayan (base 20)
𝋣·𝋠·𝋯
Chinese
一千二百一十五
Chinese (financial)
壹仟貳佰壹拾伍
In other modern scripts
Eastern Arabic ١٢١٥ Devanagari १२१५ Bengali ১২১৫ Tamil ௧௨௧௫ Thai ๑๒๑๕ Tibetan ༡༢༡༥ Khmer ១២១៥ Lao ໑໒໑໕ Burmese ၁၂၁၅

Digit at this position in famous constants

π — Pi (π)
Digit 1,215 = 0
e — Euler's number (e)
Digit 1,215 = 8
φ — Golden ratio (φ)
Digit 1,215 = 4
√2 — Pythagoras's (√2)
Digit 1,215 = 1
ln 2 — Natural log of 2
Digit 1,215 = 7
γ — Euler-Mascheroni (γ)
Digit 1,215 = 4

Also seen as

Unicode codepoint
ҿ
Cyrillic Small Letter Abkhasian Che With Descender
U+04BF
Lowercase letter (Ll)

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

Hex color
#0004BF
RGB(0, 4, 191)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.4.191.

Address
0.0.4.191
Class
reserved
IPv4-mapped IPv6
::ffff:0.0.4.191

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

Position in π

The digit sequence 1215 first appears in π at position 11,941 of the decimal expansion (the 11,941ordinal-suffix:st 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.