Live analysis

2,640

2,640 is a composite number, even.

This number doesn't have a permanent NumberWiki page yet — what you see below is computed live. Pages get added to the permanent index when they're notable (years, primes, curated, etc.).

Abundant Number Harshad / Niven Octagonal

Properties

Parity: Even
Digit count: 4
Digit sum: 12
Digital root: 3
Palindrome: No
Reversed: 462
Divisor count: 40
σ(n) — sum of divisors: 8,928

Primality

Prime factorization: 2 ⁴ × 3 × 5 × 11

Divisors & multiples

All divisors (40)

1 · 2 · 3 · 4 · 5 · 6 · 8 · 10 · 11 · 12 · 15 · 16 · 20 · 22 · 24 · 30 · 33 · 40 · 44 · 48 · 55 · 60 · 66 · 80 · 88 · 110 · 120 · 132 · 165 · 176 · 220 · 240 · 264 · 330 · 440 · 528 · 660 · 880 · 1320 · 2640

Aliquot sum (sum of proper divisors): 6,288

Factor pairs (a × b = 2,640)

1 × 2640

2 × 1320

3 × 880

4 × 660

5 × 528

6 × 440

8 × 330

10 × 264

11 × 240

12 × 220

15 × 176

16 × 165

20 × 132

22 × 120

24 × 110

30 × 88

33 × 80

40 × 66

44 × 60

48 × 55

First multiples

2,640 · 5,280 · 7,920 · 10,560 · 13,200 · 15,840 · 18,480 · 21,120 · 23,760 · 26,400

Representations

In words: two thousand six hundred forty
Ordinal: 2640th
Roman numeral: MMDCXL
Binary: 101001010000
Octal: 5120
Hexadecimal: 0xA50
Base64: ClA=

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 2640, here are decompositions:

7 + 2633 = 2640
19 + 2621 = 2640
23 + 2617 = 2640
31 + 2609 = 2640
47 + 2593 = 2640
61 + 2579 = 2640
83 + 2557 = 2640
89 + 2551 = 2640

Showing the first eight; more decompositions exist.

Hex color

#000A50

RGB(0, 10, 80)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.10.80.

Address: 0.0.10.80
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.10.80

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