Number

420

420 — Cannabis Counterculture

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

Four hundred twenty is widely associated with cannabis culture, originating with a group of California high schoolers in the early 1970s who would meet at 4:20 PM to smoke. It is also the sum of four consecutive primes (101 + 103 + 107 + 109).

Sources https://en.wikipedia.org/wiki/420_(cannabis_culture)

Abundant Number Curated Harshad / Niven Pronic / Oblong

Properties

Parity: Even
Digit count: 3
Digit sum: 6
Digital root: 6
Palindrome: No
Divisor count: 24
σ(n) — sum of divisors: 1,344

Primality

Prime factorization: 2 ² × 3 × 5 × 7

Divisors & multiples

All divisors (24)

1 · 2 · 3 · 4 · 5 · 6 · 7 · 10 · 12 · 14 · 15 · 20 · 21 · 28 · 30 · 35 · 42 · 60 · 70 · 84 · 105 · 140 · 210 · 420

Aliquot sum (sum of proper divisors): 924

Factor pairs (a × b = 420)

1 × 420

2 × 210

3 × 140

4 × 105

5 × 84

6 × 70

7 × 60

10 × 42

12 × 35

14 × 30

15 × 28

20 × 21

First multiples

420 · 840 · 1,260 · 1,680 · 2,100 · 2,520 · 2,940 · 3,360 · 3,780 · 4,200

Representations

In words: four hundred twenty
Ordinal: 420th
Roman numeral: CDXX
Binary: 110100100
Octal: 644
Hexadecimal: 1A4

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 420, here are decompositions:

11 + 409 = 420
19 + 401 = 420
23 + 397 = 420
31 + 389 = 420
37 + 383 = 420
41 + 379 = 420
47 + 373 = 420
53 + 367 = 420

Showing the first eight; more decompositions exist.

Unicode codepoint

U+01A4

Uppercase letter (Lu)

UTF-8 encoding: C6 A4 (2 bytes).

Lookup U+01A4 on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#0001A4

RGB(0, 1, 164)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.1.164.