Number

990

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

Abundant Number Harshad / Niven Triangular Year

Properties

Parity: Even
Digit count: 3
Digit sum: 18
Digital root: 9
Palindrome: No
Divisor count: 24
σ(n) — sum of divisors: 2,808

Primality

Prime factorization: 2 × 3 ² × 5 × 11

Divisors & multiples

All divisors (24)

1 · 2 · 3 · 5 · 6 · 9 · 10 · 11 · 15 · 18 · 22 · 30 · 33 · 45 · 55 · 66 · 90 · 99 · 110 · 165 · 198 · 330 · 495 · 990

Aliquot sum (sum of proper divisors): 1,818

Factor pairs (a × b = 990)

1 × 990

2 × 495

3 × 330

5 × 198

6 × 165

9 × 110

10 × 99

11 × 90

15 × 66

18 × 55

22 × 45

30 × 33

First multiples

990 · 1,980 · 2,970 · 3,960 · 4,950 · 5,940 · 6,930 · 7,920 · 8,910 · 9,900

Representations

In words: nine hundred ninety
Ordinal: 990th
Roman numeral: CMXC
Binary: 1111011110
Octal: 1736
Hexadecimal: 3DE

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 990, here are decompositions:

7 + 983 = 990
13 + 977 = 990
19 + 971 = 990
23 + 967 = 990
37 + 953 = 990
43 + 947 = 990
53 + 937 = 990
61 + 929 = 990

Showing the first eight; more decompositions exist.

Unicode codepoint

U+03DE

Uppercase letter (Lu)

UTF-8 encoding: CF 9E (2 bytes).

Lookup U+03DE on Compart ↗ Lookup on FileFormat.Info ↗

Network port

TCP/UDP port 990 is the well-known port for FTPS — FTP over TLS — control channel.

Hex color

#0003DE

RGB(0, 3, 222)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.3.222.

Possible US bank routing number

This passes the ABA routing number checksum and matches the Federal Reserve numbering scheme.

Routing number

000000990

Federal Reserve

United States Government

Banks operate many routing numbers per state and division; an unmatched checksum-valid number can still be a real RTN at a smaller institution.

Look up 000000990 on FedACH ↗ Routing Number Lookup (Wise) ↗