1089 (number)

From Wikipedia, the free encyclopedia

1089 is the integer after 1088 and before 1090.

List of numbers — Integers ← 1k 2k 3k 4k 5k 6k 7k 8k 9k →
1089
Cardinal	One thousand and eighty-nine
Ordinal	1089th
Factorization
Binary	10001000001
Hexadecimal	441

It is a square number (33 squared), a nonagonal number, a 32-gonal number, a 364-gonal number, and a centered octagonal number.

In base 10, the following steps always yield 1089:

1. Take any three-digit integer in which the first digit is at least two more than the last.
2. Reverse the digits, and subtract the result from the original number.
3. Add to this result the number produced by reversing its digits.

For example:

732 - 237 = 495
495 + 594 = 1089

Multiplying the number 1089 by the integers from 1 to 9 produces a pattern: multipliers adding up to 10 give products that are the digit reversals of each other.

1 x 1089 = 1089
2 x 1089 = 2178
3 x 1089 = 3267
4 x 1089 = 4356
5 x 1089 = 5445
6 x 1089 = 6534
7 x 1089 = 7623
8 x 1089 = 8712
9 x 1089 = 9801

Numbers formed analogously in other bases, e.g. octal 1067 or hexadecimal 10EF, also have these properties.

[edit] Other uses

• In the Rich Text Format, the language code 1089 indicates the text is in Swahili.