Number

1,428

1,428 is a composite number, even, a calendar year.

1,428 (one thousand four hundred twenty-eight) is an even 4-digit number. It is a composite number with 24 divisors, and factors as 2² × 3 × 7 × 17. Its proper divisors sum to 2,604, more than the number itself, making it an abundant number. Written other ways, in Roman numerals it is MCDXXVIII and in binary, 10110010100.

Abundant Number Arithmetic Number Cube-Free Odious Number Pernicious Number Practical Number Recamán's Sequence Semiperfect Number Year

Interestingness

★ ★ ★ ☆ ☆

5 notable facts · grade C

1,416 1,417 1,418 1,419 1,420 1,421 1,422 1,423 1,424 1,425 1,426 1,427 1,428 1,429 1,430 1,431 1,432 1,433 1,434 1,435 1,436 1,437 1,438 1,439 1,440

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Historical context — 1428 AD

Calendar year

Year 1428 (MCDXXVIII) 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 →

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: Tuesday
January 1, 1428
Ended on: Wednesday
December 31, 1428
Friday the 13ths: 1
One Friday the 13th this year.
Decade: 1420s
1420–1429
Century: 15th century
1401–1500
Millennium: 2nd millennium
1001–2000
Years ago: 598
598 years before 2026.

In other calendars

Hebrew: 5188 / 5189 AM
Rosh Hashanah falls in September/October.
Islamic Hijri: 831 / 832 AH
Lunar calendar; year spans differ from Gregorian.
Chinese: Year of the zodiac:Earth zodiac:Monkey
Sexagenary cycle position 45 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 1971 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri: 806 / 807 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian: 1420 / 1421 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 1350 / 1349 Saka
Indian national calendar; year starts in March.

Properties

Parity: Even
Digit count: 4
Digit sum: 15
Digit product: 64
Digital root: 6
Palindrome: No
Bit width: 11 bits
Reversed: 8,241
Recamán's sequence: a(1,704) = 1,428
Square (n²): 2,039,184
Cube (n³): 2,911,954,752
Divisor count: 24
σ(n) — sum of divisors: 4,032
φ(n) — Euler's totient: 384
Sum of prime factors: 31

Primality

Prime factorization: 2 ² × 3 × 7 × 17

Nearest primes: 1,427 (−1) · 1,429 (+1)

Divisors & multiples

All divisors (24)

1 · 2 · 3 · 4 · 6 · 7 · 12 · 14 · 17 · 21 · 28 · 34 · 42 · 51 · 68 · 84 · 102 · 119 · 204 · 238 · 357 · 476 · 714 (half) · 1428

Aliquot sum (sum of proper divisors): 2,604

Factor pairs (a × b = 1,428)

1 × 1428

2 × 714

3 × 476

4 × 357

6 × 238

7 × 204

12 × 119

14 × 102

17 × 84

21 × 68

28 × 51

34 × 42

First multiples

1,428 · 2,856 (double) · 4,284 · 5,712 · 7,140 · 8,568 · 9,996 · 11,424 · 12,852 · 14,280

Sums & aliquot sequence

As consecutive integers: 475 + 476 + 477 201 + 202 + … + 207 175 + 176 + … + 182 76 + 77 + … + 92

Aliquot sequence: 1,428 → 2,604 → 4,564 → 4,620 → 11,508 → 19,404 → 42,840 → 125,640 → 283,860 → 633,420 → 1,562,004 → 2,535,180 → 5,206,260 → 9,371,436 → 12,495,276 → 20,190,804 → 26,921,100 — unresolved within range

Continued fraction of √n

√1,428 = [37; (1, 3, 1, 2, 1, 3, 1, 74)]

Period length 8 — the block in parentheses repeats forever.

Representations

In words: one thousand four hundred twenty-eight
Ordinal: 1428th
Roman numeral: MCDXXVIII
Binary: 10110010100
Octal: 2624
Hexadecimal: 0x594
Base64: BZQ=
One's complement: 64,107 (16-bit)
Scientific notation: 1.428 × 10³
As a duration: 1,428 s = 23 minutes, 48 seconds

In other bases

ternary (3) 1221220

quaternary (4) 112110

quinary (5) 21203

senary (6) 10340

septenary (7) 4110

nonary (9) 1856

undecimal (11) 1089

duodecimal (12) 9b0

tridecimal (13) 85b

tetradecimal (14) 740

pentadecimal (15) 653

As an angle

1,428° = 3 × 360° + 348°

348° ≈ 6.074 rad

Compass bearing: NNW (north-northwest)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒌋𒌋𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹
Egyptian hieroglyphic: 𓆼𓍢𓍢𓍢𓍢𓎆𓎆𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺
Greek (Milesian): ͵αυκηʹ
Mayan (base 20): 𝋣·𝋫·𝋨
Chinese: 一千四百二十八
Chinese (financial): 壹仟肆佰貳拾捌

In other modern scripts

Eastern Arabic ١٤٢٨ Devanagari १४२८ Bengali ১৪২৮ Tamil ௧௪௨௮ Thai ๑๔๒๘ Tibetan ༡༤༢༨ Khmer ១៤២៨ Lao ໑໔໒໘ Burmese ၁၄၂၈

Digit at this position in famous constants

π — Pi (π): Digit 1,428 = 1
e — Euler's number (e): Digit 1,428 = 5
φ — Golden ratio (φ): Digit 1,428 = 5
√2 — Pythagoras's (√2): Digit 1,428 = 5
ln 2 — Natural log of 2: Digit 1,428 = 2
γ — Euler-Mascheroni (γ): Digit 1,428 = 4

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 1428, here are decompositions:

5 + 1423 = 1428
19 + 1409 = 1428
29 + 1399 = 1428
47 + 1381 = 1428
61 + 1367 = 1428
67 + 1361 = 1428
101 + 1327 = 1428
107 + 1321 = 1428

Showing the first eight; more decompositions exist.

Unicode codepoint

Hebrew Accent Zaqef Qatan

U+0594

Non-spacing mark (Mn)

UTF-8 encoding: D6 94 (2 bytes).

Lookup U+0594 on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#000594

RGB(0, 5, 148)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.5.148.

Address: 0.0.5.148
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.5.148

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

Musical pitch

Heard as a frequency, 1,428 Hz is closest to:

Concert pitch (A4 = 440 Hz): F6 (1396.9 Hz, +38¢)
Scientific pitch (C4 = 256 Hz): F♯6 (1448.2 Hz, -24¢)
Baroque pitch (A4 = 415 Hz): F♯6 (1395.9 Hz, +39¢)

Position in π

The digit sequence 1428 first appears in π at position 3,757 of the decimal expansion (the 3,757ordinal-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 1428 on Pi Search ↗