2,015
2,015 is a composite number, odd, a calendar year.
Notable events — 2015 AD
- Jan 7 Gunmen attack the offices of satirical magazine Charlie Hebdo in Paris.
- Apr 25 A magnitude 7.8 earthquake strikes Nepal, killing nearly 9,000.
- Jul 14 Iran agrees to long-term limits on its nuclear program in exchange for sanctions relief.
- Jul 14 NASA's New Horizons probe completes the first flyby of Pluto.
- Jul 20 The United States and Cuba restore full diplomatic relations after 54 years.
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, 2015
- Ended on
-
Thursday
December 31, 2015
- Friday the 13ths
-
3
3 Friday the 13ths this year.
- Easter Sunday
-
April 5
Sunday, April 5, 2015
- Decade
-
2010s
2010–2019
- Century
-
21st century
2001–2100
- Millennium
-
3rd millennium
2001–3000
- Years ago
-
11
11 years before 2026.
In other calendars
- Hebrew
-
5775 / 5776 AM
Rosh Hashanah falls in September/October.
- Islamic Hijri
-
1436 / 1437 AH
Lunar calendar; year spans differ from Gregorian.
- Chinese
-
Year of the zodiac:Wood zodiac:Goat
Sexagenary cycle position 32 of 60. Lunar new year falls in late January / mid-February.
- Buddhist Era
-
2558 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
- Persian Solar Hijri
-
1393 / 1394 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
- Ethiopian
-
2007 / 2008 ET
Year boundary at Enkutatash (September 11/12).
- Indian National (Saka)
-
1937 / 1936 Saka
Indian national calendar; year starts in March.
- Japanese
-
Heisei 27
Reign-era counting from the start of each emperor's reign.
Properties
- Parity
- Odd
- Digit count
- 4
- Digit sum
- 8
- Digit product
- 0
- Digital root
- 8
- Palindrome
- No
- Bit width
- 11 bits
- Reversed
- 5,102
- Recamán's sequence
- a(3,721) = 2,015
- Square (n²)
- 4,060,225
- Cube (n³)
- 8,181,353,375
- Divisor count
- 8
- σ(n) — sum of divisors
- 2,688
- φ(n) — Euler's totient
- 1,440
- Sum of prime factors
- 49
Primality
Prime factorization: 5 × 13 × 31
Divisors & multiples
Sums & aliquot sequence
Representations
- In words
- two thousand fifteen
- Ordinal
- 2015th
- Roman numeral
- MMXV
- Binary
- 11111011111
- Octal
- 3737
- Hexadecimal
- 0x7DF
- Base64
- B98=
- One's complement
- 63,520 (16-bit)
Historical numeral systems
- Babylonian (base 60)
- 𒌋𒌋𒌋𒁹𒁹𒁹 𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹
- Egyptian hieroglyphic
- 𓆼𓆼𓎆𓏺𓏺𓏺𓏺𓏺
- Greek (Milesian)
- ͵βιεʹ
- Mayan (base 20)
- 𝋥·𝋠·𝋯
- Chinese
- 二千零一十五
- Chinese (financial)
- 貳仟零壹拾伍
Digit at this position in famous constants
- π — Pi (π)
- Digit 2,015 = 2
- e — Euler's number (e)
- Digit 2,015 = 2
- φ — Golden ratio (φ)
- Digit 2,015 = 3
- √2 — Pythagoras's (√2)
- Digit 2,015 = 7
- ln 2 — Natural log of 2
- Digit 2,015 = 5
- γ — Euler-Mascheroni (γ)
- Digit 2,015 = 0
Also seen as
UTF-8 encoding: DF 9F (2 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.7.223.
- Address
- 0.0.7.223
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.7.223
Unspecified address (0.0.0.0/8) — "this network" placeholder.
The digit sequence 2015 first appears in π at position 19,038 of the decimal expansion (the 19,038ordinal-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.