Number

156

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

156 (one hundred fifty-six) is an even 3-digit number. It is a composite number with 12 divisors, and factors as 2² × 3 × 13. Its proper divisors sum to 236, more than the number itself, making it an abundant number. Written other ways, in Roman numerals it is CLVI and in binary, 10011100.

Abundant Number Ascending Digits Cube-Free Evil Number Harshad / Niven Moran Number Practical Number Pronic / Oblong Recamán's Sequence Refactorable Number Semiperfect Number Year

Interestingness

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9 notable facts · grade A

144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168

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Historical context — 156 AD

Calendar year

Year 156 (CLVI) was a leap year starting on Wednesday of the Julian calendar.

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

Historical context — 156 BC

Calendar year

Year 156 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: 53
Long year: contains 53 ISO weeks.
Started on: Thursday
January 1, 156
Ended on: Friday
December 31, 156
Friday the 13ths: 2
2 Friday the 13ths this year.
Decade: 150s
150–159
Century: 2nd century
101–200
Millennium: 1st millennium
1–1000
Years ago: 1,870
1870 years before 2026.

In other calendars

Hebrew: 3916 / 3917 AM
Rosh Hashanah falls in September/October.
Chinese: Year of the zodiac:Fire zodiac:Monkey
Sexagenary cycle position 33 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 699 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Ethiopian: 148 / 149 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 78 / 77 Saka
Indian national calendar; year starts in March.

Properties

Parity: Even
Digit count: 3
Digit sum: 12
Digit product: 30
Digital root: 3
Palindrome: No
Bit width: 8 bits
Reversed: 651
Recamán's sequence: a(68) = 156
Square (n²): 24,336
Cube (n³): 3,796,416
Divisor count: 12
σ(n) — sum of divisors: 392
φ(n) — Euler's totient: 48
Sum of prime factors: 20

Primality

Prime factorization: 2 ² × 3 × 13

Nearest primes: 151 (−5) · 157 (+1)

Divisors & multiples

All divisors (12)

1 · 2 · 3 · 4 · 6 · 12 · 13 · 26 · 39 · 52 · 78 (half) · 156

Aliquot sum (sum of proper divisors): 236

Factor pairs (a × b = 156)

1 × 156

2 × 78

3 × 52

4 × 39

6 × 26

12 × 13

First multiples

156 · 312 (double) · 468 · 624 · 780 · 936 · 1,092 · 1,248 · 1,404 · 1,560

Sums & aliquot sequence

As consecutive integers: 51 + 52 + 53 16 + 17 + … + 23 6 + 7 + … + 18

Aliquot sequence: 156 → 236 → 184 → 176 → 196 → 203 → 37 → 1 → 0 — terminates at zero

Continued fraction of √n

√156 = [12; (2, 24)]

Period length 2 — the block in parentheses repeats forever.

Representations

In words: one hundred fifty-six
Ordinal: 156th
Roman numeral: CLVI
Binary: 10011100
Octal: 234
Hexadecimal: 0x9C
Base64: nA==
One's complement: 99 (8-bit)
Scientific notation: 1.56 × 10²
As a duration: 156 s = 2 minutes, 36 seconds

In other bases

ternary (3) 12210

quaternary (4) 2130

quinary (5) 1111

senary (6) 420

septenary (7) 312

nonary (9) 183

undecimal (11) 132

duodecimal (12) 110

tridecimal (13) c0

tetradecimal (14) b2

pentadecimal (15) a6

Palindromic in base 5

As an angle

156°

156° ≈ 2.723 rad

Compass bearing: SSE (south-southeast)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒁹𒁹 𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹
Egyptian hieroglyphic: 𓍢𓎆𓎆𓎆𓎆𓎆𓏺𓏺𓏺𓏺𓏺𓏺
Greek (Milesian): ρνϛʹ
Mayan (base 20): 𝋧·𝋰
Chinese: 一百五十六
Chinese (financial): 壹佰伍拾陸

In other modern scripts

Eastern Arabic ١٥٦ Devanagari १५६ Bengali ১৫৬ Tamil ௧௫௬ Thai ๑๕๖ Tibetan ༡༥༦ Khmer ១៥៦ Lao ໑໕໖ Burmese ၁၅၆

Digit at this position in famous constants

π — Pi (π): Digit 156 = 1
e — Euler's number (e): Digit 156 = 3
φ — Golden ratio (φ): Digit 156 = 5
√2 — Pythagoras's (√2): Digit 156 = 3
ln 2 — Natural log of 2: Digit 156 = 6
γ — Euler-Mascheroni (γ): Digit 156 = 3

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 156, here are decompositions:

5 + 151 = 156
7 + 149 = 156
17 + 139 = 156
19 + 137 = 156
29 + 127 = 156
43 + 113 = 156
47 + 109 = 156
53 + 103 = 156

Showing the first eight; more decompositions exist.

Unicode codepoint

String Terminator

U+009C

Control character (Cc)

UTF-8 encoding: C2 9C (2 bytes).

Lookup U+009C on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#00009C

RGB(0, 0, 156)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.156.

Address: 0.0.0.156
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.0.156

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

Musical pitch

Heard as a frequency, 156 Hz is closest to:

Concert pitch (A4 = 440 Hz): D♯3 (155.6 Hz, +5¢)
Scientific pitch (C4 = 256 Hz): D♯3 (152.2 Hz, +42¢)
Baroque pitch (A4 = 415 Hz): E3 (155.4 Hz, +6¢)