Number

56

56 is a composite number, even, a calendar year.

56 (fifty-six) is an even 2-digit number. It is a composite number with 8 divisors, and factors as 2³ × 7. Its proper divisors sum to 64, more than the number itself, making it an abundant number. Written other ways, in Roman numerals it is LVI and in binary, 111000.

Abundant Number Arithmetic Number Lazy Caterer Number Odious Number Partition Number Pernicious Number Practical Number Preferred Number Pronic / Oblong Recamán's Sequence Refactorable Number Semiperfect Number Tetrahedral Tetranacci Number Year

Interestingness

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11 notable facts · grade A

44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68

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Historical context — 56 AD

Calendar year

AD 56 (LVI) was a leap year starting on Thursday of the Julian calendar.

Excerpt from Wikipedia (en) ↗ · Licensed CC BY-SA 4.0 Read the full article on Wikipedia →

Historical context — 56 BC

Calendar year

Year 56 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: Leap year
Divisible by 4 and not by 100; February has 29 days.
Days in year: 366
ISO weeks: 52
Started on: Saturday
January 1, 56
Ended on: Sunday
December 31, 56
Friday the 13ths: 1
One Friday the 13th this year.
Decade: 50s
50–59
Century: 1st century
1–100
Millennium: 1st millennium
1–1000
Years ago: 1,970
1970 years before 2026.

In other calendars

Hebrew: 3816 / 3817 AM
Rosh Hashanah falls in September/October.
Chinese: Year of the zodiac:Fire zodiac:Dragon
Sexagenary cycle position 53 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 599 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Ethiopian: 48 / 49 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): -22 / -23 Saka
Indian national calendar; year starts in March.

Properties

Parity: Even
Digit count: 2
Digit sum: 11
Digit product: 30
Digital root: 2
Palindrome: No
Bit width: 6 bits
Reversed: 65
Recamán's sequence: a(204) = 56
Square (n²): 3,136
Cube (n³): 175,616
Divisor count: 8
σ(n) — sum of divisors: 120
φ(n) — Euler's totient: 24
Sum of prime factors: 13

Primality

Prime factorization: 2 ³ × 7

Nearest primes: 53 (−3) · 59 (+3)

Divisors & multiples

All divisors (8)

1 · 2 · 4 · 7 · 8 · 14 · 28 (half) · 56

Aliquot sum (sum of proper divisors): 64

Factor pairs (a × b = 56)

1 × 56

2 × 28

4 × 14

7 × 8

First multiples

56 · 112 (double) · 168 · 224 · 280 · 336 · 392 · 448 · 504 · 560

Sums & aliquot sequence

As consecutive integers: 5 + 6 + … + 11

Aliquot sequence: 56 → 64 → 63 → 41 → 1 → 0 — terminates at zero

Continued fraction of √n

√56 = [7; (2, 14)]

Period length 2 — the block in parentheses repeats forever.

Representations

In words: fifty-six
Ordinal: 56th
Roman numeral: LVI
Binary: 111000
Octal: 70
Hexadecimal: 0x38
Base64: OA==
One's complement: 199 (8-bit)
Scientific notation: 5.6 × 10¹

In other bases

ternary (3) 2002

quaternary (4) 320

quinary (5) 211

senary (6) 132

septenary (7) 110

nonary (9) 62

undecimal (11) 51

duodecimal (12) 48

tridecimal (13) 44

tetradecimal (14) 40

pentadecimal (15) 3b

Palindromic in base 3

As an angle

56°

56° ≈ 0.977 rad

Compass bearing: NE (northeast)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒌋𒌋𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹
Egyptian hieroglyphic: 𓎆𓎆𓎆𓎆𓎆𓏺𓏺𓏺𓏺𓏺𓏺
Greek (Milesian): νϛʹ
Mayan (base 20): 𝋢·𝋰
Chinese: 五十六
Chinese (financial): 伍拾陸

In other modern scripts

Eastern Arabic ٥٦ Devanagari ५६ Bengali ৫৬ Tamil ௫௬ Thai ๕๖ Tibetan ༥༦ Khmer ៥៦ Lao ໕໖ Burmese ၅၆

Digit at this position in famous constants

π — Pi (π): Digit 56 = 9
e — Euler's number (e): Digit 56 = 9
φ — Golden ratio (φ): Digit 56 = 1
√2 — Pythagoras's (√2): Digit 56 = 1
ln 2 — Natural log of 2: Digit 56 = 1
γ — Euler-Mascheroni (γ): Digit 56 = 8

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 56, here are decompositions:

3 + 53 = 56
13 + 43 = 56
19 + 37 = 56

ASCII character

As an ASCII codepoint, 56 is 8. Printable ASCII character 8.

Hex color

#000038

RGB(0, 0, 56)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.56.

Address: 0.0.0.56
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.0.56

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

Musical pitch

Heard as a frequency, 56 Hz is closest to:

Concert pitch (A4 = 440 Hz): A1 (55 Hz, +31¢)
Scientific pitch (C4 = 256 Hz): A♯1 (57 Hz, -31¢)
Baroque pitch (A4 = 415 Hz): A♯1 (55 Hz, +32¢)

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

As a MIDI note number, 56 is G♯3 (207.7 Hz at concert pitch).

Atomic number

On the periodic table, atomic number 56 is Barium (Ba) — period 6.

Barium on Wikipedia ↗