Number

3,121

3,121 is a prime, odd.

3,121 (three thousand one hundred twenty-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 MMMCXXI and in binary, 110000110001.

Arithmetic Number Centered Square Cube-Free Deficient Number Emirp Odious Number Pernicious Number Prime Pythagorean Prime Recamán's Sequence Squarefree Twin Prime

Interestingness

★ ★ ★ ★ ★

9 notable facts · grade A

3,109 3,110 3,111 3,112 3,113 3,114 3,115 3,116 3,117 3,118 3,119 3,120 3,121 3,122 3,123 3,124 3,125 3,126 3,127 3,128 3,129 3,130 3,131 3,132 3,133

less more

Properties

Parity: Odd
Digit count: 4
Digit sum: 7
Digit product: 6
Digital root: 7
Palindrome: No
Bit width: 12 bits
Reversed: 1,213
Recamán's sequence: a(1,681) = 3,121
Square (n²): 9,740,641
Cube (n³): 30,400,540,561
Divisor count: 2
σ(n) — sum of divisors: 3,122
φ(n) — Euler's totient: 3,120

Primality

3,121 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)

1 · 3121

Aliquot sum (sum of proper divisors): 1

Factor pairs (a × b = 3,121)

1 × 3121

First multiples

3,121 · 6,242 (double) · 9,363 · 12,484 · 15,605 · 18,726 · 21,847 · 24,968 · 28,089 · 31,210

Sums & aliquot sequence

As a sum of two squares: 39² + 40²

As consecutive integers: 1,560 + 1,561

Continued fraction of √n

√3,121 = [55; (1, 6, 2, 5, 2, 2, 2, 2, 5, 2, 6, 1, 110)]

Period length 13 — the block in parentheses repeats forever.

Representations

In words: three thousand one hundred twenty-one
Ordinal: 3121st
Roman numeral: MMMCXXI
Binary: 110000110001
Octal: 6061
Hexadecimal: 0xC31
Base64: DDE=
One's complement: 62,414 (16-bit)
Scientific notation: 3.121 × 10³
As a duration: 3,121 s = 52 minutes, 1 second

In other bases

ternary (3) 11021121

quaternary (4) 300301

quinary (5) 44441

senary (6) 22241

septenary (7) 12046

nonary (9) 4247

undecimal (11) 2388

duodecimal (12) 1981

tridecimal (13) 1561

tetradecimal (14) 11cd

pentadecimal (15) dd1

As an angle

3,121° = 8 × 360° + 241°

241° ≈ 4.206 rad

Compass bearing: WSW (west-southwest)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒌋𒌋𒌋𒌋𒌋𒁹𒁹 𒁹
Egyptian hieroglyphic: 𓆼𓆼𓆼𓍢𓎆𓎆𓏺
Greek (Milesian): ͵γρκαʹ
Mayan (base 20): 𝋧·𝋰·𝋡
Chinese: 三千一百二十一
Chinese (financial): 參仟壹佰貳拾壹

In other modern scripts

Eastern Arabic ٣١٢١ Devanagari ३१२१ Bengali ৩১২১ Tamil ௩௧௨௧ Thai ๓๑๒๑ Tibetan ༣༡༢༡ Khmer ៣១២១ Lao ໓໑໒໑ Burmese ၃၁၂၁

Digit at this position in famous constants

π — Pi (π): Digit 3,121 = 2
e — Euler's number (e): Digit 3,121 = 8
φ — Golden ratio (φ): Digit 3,121 = 6
√2 — Pythagoras's (√2): Digit 3,121 = 4
ln 2 — Natural log of 2: Digit 3,121 = 9
γ — Euler-Mascheroni (γ): Digit 3,121 = 5

Also seen as

Prime neighborhood

Adjacent primes:

Previous prime: 3,119 (gap of 2)
Next prime: 3,137 (gap of 16)

Pair status: twin with 3119.

Unicode codepoint

ఱ

Telugu Letter Rra

U+0C31

Other letter (Lo)

UTF-8 encoding: E0 B0 B1 (3 bytes).

Lookup U+0C31 on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#000C31

RGB(0, 12, 49)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.12.49.

Address: 0.0.12.49
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.12.49

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

Musical pitch

Heard as a frequency, 3,121 Hz is closest to:

Concert pitch (A4 = 440 Hz): G7 (3136 Hz, -8¢)
Scientific pitch (C4 = 256 Hz): G7 (3068.5 Hz, +29¢)
Baroque pitch (A4 = 415 Hz): G♯7 (3133.7 Hz, -7¢)

Position in π

The digit sequence 3121 first appears in π at position 20,088 of the decimal expansion (the 20,088ordinal-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 3121 on Pi Search ↗