Number

3,181

3,181 is a prime, odd.

3,181 (three thousand one hundred eighty-one) is an odd 4-digit number. It is a prime number — divisible only by 1 and itself. Written other ways, in Roman numerals it is MMMCLXXXI and in binary, 110001101101.

Arithmetic Number Chen Prime Cube-Free Deficient Number Odious Number Pernicious Number Prime Pythagorean Prime Recamán's Sequence Sexy Prime Squarefree

Interestingness

★ ★ ★ ★ ★

8 notable facts · grade A

3,169 3,170 3,171 3,172 3,173 3,174 3,175 3,176 3,177 3,178 3,179 3,180 3,181 3,182 3,183 3,184 3,185 3,186 3,187 3,188 3,189 3,190 3,191 3,192 3,193

less more

Properties

Parity: Odd
Digit count: 4
Digit sum: 13
Digit product: 24
Digital root: 4
Palindrome: No
Bit width: 12 bits
Reversed: 1,813
Recamán's sequence: a(6,986) = 3,181
Square (n²): 10,118,761
Cube (n³): 32,187,778,741
Divisor count: 2
σ(n) — sum of divisors: 3,182
φ(n) — Euler's totient: 3,180

Primality

3,181 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)

1 · 3181

Aliquot sum (sum of proper divisors): 1

Factor pairs (a × b = 3,181)

1 × 3181

First multiples

3,181 · 6,362 (double) · 9,543 · 12,724 · 15,905 · 19,086 · 22,267 · 25,448 · 28,629 · 31,810

Sums & aliquot sequence

As a sum of two squares: 34² + 45²

As consecutive integers: 1,590 + 1,591

Continued fraction of √n

√3,181 = [56; (2, 2, 112)]

Period length 3 — the block in parentheses repeats forever.

Representations

In words: three thousand one hundred eighty-one
Ordinal: 3181st
Roman numeral: MMMCLXXXI
Binary: 110001101101
Octal: 6155
Hexadecimal: 0xC6D
Base64: DG0=
One's complement: 62,354 (16-bit)
Scientific notation: 3.181 × 10³
As a duration: 3,181 s = 53 minutes, 1 second

In other bases

ternary (3) 11100211

quaternary (4) 301231

quinary (5) 100211

senary (6) 22421

septenary (7) 12163

nonary (9) 4324

undecimal (11) 2432

duodecimal (12) 1a11

tridecimal (13) 15a9

tetradecimal (14) 1233

pentadecimal (15) e21

As an angle

3,181° = 8 × 360° + 301°

301° ≈ 5.253 rad

Compass bearing: WNW (west-northwest)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒌋𒌋𒌋𒌋𒌋𒁹𒁹𒁹 𒁹
Egyptian hieroglyphic: 𓆼𓆼𓆼𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺
Greek (Milesian): ͵γρπαʹ
Mayan (base 20): 𝋧·𝋳·𝋡
Chinese: 三千一百八十一
Chinese (financial): 參仟壹佰捌拾壹

In other modern scripts

Eastern Arabic ٣١٨١ Devanagari ३१८१ Bengali ৩১৮১ Tamil ௩௧௮௧ Thai ๓๑๘๑ Tibetan ༣༡༨༡ Khmer ៣១៨១ Lao ໓໑໘໑ Burmese ၃၁၈၁

Digit at this position in famous constants

π — Pi (π): Digit 3,181 = 4
e — Euler's number (e): Digit 3,181 = 2
φ — Golden ratio (φ): Digit 3,181 = 5
√2 — Pythagoras's (√2): Digit 3,181 = 0
ln 2 — Natural log of 2: Digit 3,181 = 0
γ — Euler-Mascheroni (γ): Digit 3,181 = 4

Also seen as

Prime neighborhood

Adjacent primes:

Previous prime: 3,169 (gap of 12)
Next prime: 3,187 (gap of 6)

Pair status: sexy with 3187.

Unicode codepoint

౭

Telugu Digit Seven

U+0C6D

Decimal digit (Nd)

UTF-8 encoding: E0 B1 AD (3 bytes).

Lookup U+0C6D on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#000C6D

RGB(0, 12, 109)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.12.109.

Address: 0.0.12.109
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.12.109

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

Musical pitch

Heard as a frequency, 3,181 Hz is closest to:

Concert pitch (A4 = 440 Hz): G7 (3136 Hz, +25¢)
Scientific pitch (C4 = 256 Hz): G♯7 (3251 Hz, -38¢)
Baroque pitch (A4 = 415 Hz): G♯7 (3133.7 Hz, +26¢)

Position in π

The digit sequence 3181 first appears in π at position 5,313 of the decimal expansion (the 5,313ordinal-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.

Look up 3181 on Pi Search ↗