Number

63

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

63 (sixty-three) is an odd 2-digit number. It is a composite number with 6 divisors, and factors as 3² × 7. Written other ways, in Roman numerals it is LXIII and in binary, 111111.

Binary Palindrome Cube-Free Deficient Number Evil Number Harshad / Niven Moran Number Recamán's Sequence Woodall Number Year

Interestingness

★ ★ ★ ★ ☆

6 notable facts · grade B

51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75

less more

Historical context — 63 AD

Calendar year

AD 63 (LXIII) 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 →

Historical context — 63 BC

Calendar year

Year 63 BC was a year of the pre-Julian Roman 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: Monday
January 1, 63
Ended on: Monday
December 31, 63
Friday the 13ths: 2
2 Friday the 13ths this year.
Decade: 60s
60–69
Century: 1st century
1–100
Millennium: 1st millennium
1–1000
Years ago: 1,963
1963 years before 2026.

In other calendars

Hebrew: 3823 / 3824 AM
Rosh Hashanah falls in September/October.
Chinese: Year of the zodiac:Water zodiac:Pig
Sexagenary cycle position 60 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 606 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Ethiopian: 55 / 56 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): -15 / -16 Saka
Indian national calendar; year starts in March.

Properties

Parity: Odd
Digit count: 2
Digit sum: 9
Digit product: 18
Digital root: 9
Palindrome: No
Bit width: 6 bits
Reversed: 36
Recamán's sequence: a(21) = 63
Square (n²): 3,969
Cube (n³): 250,047
Divisor count: 6
σ(n) — sum of divisors: 104
φ(n) — Euler's totient: 36
Sum of prime factors: 13

Primality

Prime factorization: 3 ² × 7

Nearest primes: 61 (−2) · 67 (+4)

Divisors & multiples

All divisors (6)

1 · 3 · 7 · 9 · 21 · 63

Aliquot sum (sum of proper divisors): 41

Factor pairs (a × b = 63)

1 × 63

3 × 21

7 × 9

First multiples

63 · 126 (double) · 189 · 252 · 315 · 378 · 441 · 504 · 567 · 630

Sums & aliquot sequence

As consecutive integers: 31 + 32 20 + 21 + 22 8 + 9 + 10 + 11 + 12 + 13 6 + 7 + … + 12

Aliquot sequence: 63 → 41 → 1 → 0 — terminates at zero

Continued fraction of √n

√63 = [7; (1, 14)]

Period length 2 — the block in parentheses repeats forever.

Representations

In words: sixty-three
Ordinal: 63rd
Roman numeral: LXIII
Binary: 111111
Octal: 77
Hexadecimal: 0x3F
Base64: Pw==
One's complement: 192 (8-bit)
Scientific notation: 6.3 × 10¹
As a duration: 63 s = 1 minute, 3 seconds

In other bases

ternary (3) 2100

quaternary (4) 333

quinary (5) 223

senary (6) 143

septenary (7) 120

nonary (9) 70

undecimal (11) 58

duodecimal (12) 53

tridecimal (13) 4b

tetradecimal (14) 47

pentadecimal (15) 43

Palindromic in base 2, base 4

As an angle

63°

63° ≈ 1.1 rad

Compass bearing: ENE (east-northeast)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒁹 𒁹𒁹𒁹
Egyptian hieroglyphic: 𓎆𓎆𓎆𓎆𓎆𓎆𓏺𓏺𓏺
Greek (Milesian): ξγʹ
Mayan (base 20): 𝋣·𝋣
Chinese: 六十三
Chinese (financial): 陸拾參

In other modern scripts

Eastern Arabic ٦٣ Devanagari ६३ Bengali ৬৩ Tamil ௬௩ Thai ๖๓ Tibetan ༦༣ Khmer ៦៣ Lao ໖໓ Burmese ၆၃

Digit at this position in famous constants

π — Pi (π): Digit 63 = 9
e — Euler's number (e): Digit 63 = 2
φ — Golden ratio (φ): Digit 63 = 2
√2 — Pythagoras's (√2): Digit 63 = 3
ln 2 — Natural log of 2: Digit 63 = 0
γ — Euler-Mascheroni (γ): Digit 63 = 3

Also seen as

ASCII character

As an ASCII codepoint, 63 is ?. Printable ASCII character ?.

Hex color

#00003F

RGB(0, 0, 63)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.63.

Address: 0.0.0.63
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.0.63

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

Musical pitch

Heard as a frequency, 63 Hz is closest to:

Concert pitch (A4 = 440 Hz): B1 (61.7 Hz, +35¢)
Scientific pitch (C4 = 256 Hz): C2 (64 Hz, -27¢)
Baroque pitch (A4 = 415 Hz): C2 (61.7 Hz, +36¢)

(very low — many laptop and phone speakers can't reproduce it)

As a MIDI note number, 63 is D♯4 (311.1 Hz at concert pitch).

Atomic number

On the periodic table, atomic number 63 is Europium (Eu) — period 6.

Europium on Wikipedia ↗