number.wiki
Number

421

421 is a prime, odd, a calendar year.

Deficient Number Prime Squarefree Twin Prime Year

Properties

Parity
Odd
Digit count
3
Digit sum
7
Digital root
7
Palindrome
No
Divisor count
2
σ(n) — sum of divisors
422

Primality

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

Divisors & multiples

All divisors (2)
1 · 421
Aliquot sum (sum of proper divisors): 1
Factor pairs (a × b = 421)
1 × 421
First multiples
421 · 842 · 1,263 · 1,684 · 2,105 · 2,526 · 2,947 · 3,368 · 3,789 · 4,210

Representations

In words
four hundred twenty-one
Ordinal
421st
Roman numeral
CDXXI
Binary
110100101
Octal
645
Hexadecimal
1A5

Also seen as

Prime neighborhood

Adjacent primes:

  • Previous prime: 419 (gap of 2)
  • Next prime: 431 (gap of 10)

Pair status: twin with 419.

Unicode codepoint
ƥ
U+01A5
Lowercase letter (Ll)

UTF-8 encoding: C6 A5 (2 bytes).

Hex color
#0001A5
RGB(0, 1, 165)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.1.165.