Number

157

157 is a prime, odd, a calendar year.

Arithmetic Number Ascending Digits Balanced Prime Chen Prime Deficient Number Emirp Odious Number Pernicious Number Prime Pythagorean Prime Recamán's Sequence Sexy Prime Squarefree Year

Historical context — 157 AD

Calendar year

Year 157 (CLVII) was a common year starting on Friday of the Julian calendar.

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Historical context — 157 BC

Calendar year

Year 157 BC was a year of the pre-Julian Roman calendar.

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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: Saturday
January 1, 157
Ended on: Saturday
December 31, 157
Friday the 13ths: 1
One Friday the 13th this year.
Decade: 150s
150–159
Century: 2nd century
101–200
Millennium: 1st millennium
1–1000
Years ago: 1,869
1869 years before 2026.

In other calendars

Hebrew: 3917 / 3918 AM
Rosh Hashanah falls in September/October.
Chinese: Year of the zodiac:Fire zodiac:Rooster
Sexagenary cycle position 34 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 700 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Ethiopian: 149 / 150 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 79 / 78 Saka
Indian national calendar; year starts in March.

Properties

Parity: Odd
Digit count: 3
Digit sum: 13
Digit product: 35
Digital root: 4
Palindrome: No
Bit width: 8 bits
Reversed: 751
Recamán's sequence: a(66) = 157
Square (n²): 24,649
Cube (n³): 3,869,893
Divisor count: 2
σ(n) — sum of divisors: 158
φ(n) — Euler's totient: 156

Primality

157 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)

1 · 157

Aliquot sum (sum of proper divisors): 1

Factor pairs (a × b = 157)

1 × 157

First multiples

157 · 314 (double) · 471 · 628 · 785 · 942 · 1,099 · 1,256 · 1,413 · 1,570

Sums & aliquot sequence

As a sum of two squares: 6² + 11²

As consecutive integers: 78 + 79

Representations

In words: one hundred fifty-seven
Ordinal: 157th
Roman numeral: CLVII
Binary: 10011101
Octal: 235
Hexadecimal: 0x9D
Base64: nQ==
One's complement: 98 (8-bit)

In other bases

ternary (3) 12211

quaternary (4) 2131

quinary (5) 1112

senary (6) 421

septenary (7) 313

nonary (9) 184

undecimal (11) 133

duodecimal (12) 111

tridecimal (13) c1

tetradecimal (14) b3

pentadecimal (15) a7

Historical numeral systems

Babylonian (base 60): 𒁹𒁹 𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹
Egyptian hieroglyphic: 𓍢𓎆𓎆𓎆𓎆𓎆𓏺𓏺𓏺𓏺𓏺𓏺𓏺
Greek (Milesian): ρνζʹ
Mayan (base 20): 𝋧·𝋱
Chinese: 一百五十七
Chinese (financial): 壹佰伍拾柒

In other modern scripts

Eastern Arabic ١٥٧ Devanagari १५७ Bengali ১৫৭ Tamil ௧௫௭ Thai ๑๕๗ Tibetan ༡༥༧ Khmer ១៥៧ Lao ໑໕໗ Burmese ၁၅၇

Digit at this position in famous constants

π — Pi (π): Digit 157 = 7
e — Euler's number (e): Digit 157 = 0
φ — Golden ratio (φ): Digit 157 = 4
√2 — Pythagoras's (√2): Digit 157 = 1
ln 2 — Natural log of 2: Digit 157 = 1
γ — Euler-Mascheroni (γ): Digit 157 = 6

Also seen as

Prime neighborhood

Adjacent primes:

Previous prime: 151 (gap of 6)
Next prime: 163 (gap of 6)

Pair status: sexy with 151, sexy with 163.

Unicode codepoint

Operating System Command

U+009D

Control character (Cc)

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

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

Hex color

#00009D

RGB(0, 0, 157)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.157.

Address: 0.0.0.157
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.0.157

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