Number dictionary · Exact arithmetic

1089: factors and number facts

one thousand eighty-nine is an odd number and is composite. Its 9 positive divisors form 5 factor pairs.

Number JD Editorial Team · Updated 2026-10-08

In words
one thousand eighty-nine
Roman numeral
MLXXXIX
Prime factorization
3^2 × 11^2
Digital root
9

All factors of 1089

A positive factor divides 1089 with no remainder. In ascending order, the complete list is:

1, 3, 9, 11, 33, 99, 121, 363, 1089

Factor pairs

  • 1 × 1089 = 1089
  • 3 × 363 = 1089
  • 9 × 121 = 1089
  • 11 × 99 = 1089
  • 33 × 33 = 1089

Each pair describes an arrangement of 1089 items into equal rows. The 33 × 33 pair is square, so its shared factor appears only once in the factor list.

Divisor totals

Positive divisors
9
Sum of all divisors
1729
Sum excluding 1089
640
Classification
deficient

1089 is deficient because its proper divisors add to 640, which is less than 1089.

Understand factors and multiples

Prime factorization of 1089

1089 = 3^2 × 11^2

Repeated division, step by step

  1. 1089 ÷ 3 = 363
  2. 363 ÷ 3 = 121
  3. 121 ÷ 11 = 11
  4. 11 ÷ 11 = 1

Multiply the prime divisors in these steps to reconstruct 1089. An exponent records how many times the same prime occurs. The divisor-count calculation is (2 + 1) × (2 + 1) = 9.

The preceding prime is 1087. The next larger prime is 1091. The factor list above explains why 1089 is composite.

Learn the factorization method

1089 in words, Roman numerals and other bases

Equivalent representations of the integer 1089
RepresentationValue
English (US style)one thousand eighty-nine
Roman numeralMLXXXIX
Binary (base 2)10001000001
Octal (base 8)2101
Decimal (base 10)1089
Hexadecimal (base 16)441

Check the binary conversion

Read 10001000001 from right to left using place values 1, 2, 4, 8 and successive powers of two. Keep the values whose bit is 1:

1024 + 64 + 1 = 1089

Check the hexadecimal conversion

4 × 16^2 + 4 × 16^1 + 1 × 16^0 = 1089

Hexadecimal uses A through F for digit values 10 through 15. These notations represent the same quantity; changing the base does not change the integer.

Square, cube and square root of 1089

1089 squared
1089 × 1089 = 1,185,921
1089 cubed
1089 × 1089 × 1089 = 1,291,467,969
Square root
= 33
Simplified radical
33

1089 is a perfect square: 33 × 33 = 1089. It is not a perfect cube.

1089 is not triangular: no positive whole-number k satisfies k(k + 1) / 2 = 1089.

Distinguish a square from a square root

Multiplication table for 1089

These are the first twelve positive multiples. Unlike the finite factor list, the sequence of multiples continues without an upper limit.

1089 × 11,089
1089 × 22,178
1089 × 33,267
1089 × 44,356
1089 × 55,445
1089 × 66,534
1089 × 77,623
1089 × 88,712
1089 × 99,801
1089 × 1010,890
1089 × 1111,979
1089 × 1213,068

Divisibility checks

Quotients and remainders for divisors 2 through 12
Divide byWhole quotientRemainderDivides exactly?
25441No
33630Yes
42721No
52174No
61813No
71554No
81361No
91210Yes
101089No
11990Yes
12909No

For example, 1089 = 7 × 155 + 4. A remainder of zero is what makes a divisor a factor.

Digit sum and digital root of 1089

1089 contains 4 decimal digits. Its digit sum is 1 + 0 + 8 + 9 = 18.

  1. 1089: 1 + 0 + 8 + 9 = 18
  2. 18: 1 + 8 = 9

The digital root is 9. Reversing its digits gives 9801; it is not a decimal palindrome. Digit patterns depend on the notation being used.

Digital-root arithmetic always finishes at a single digit for a positive integer. Some numerology methods stop at 11, 22 or 33 instead; that is a separate interpretive convention.

Fractions and a worked comparison

As a fraction of 100, 1089/100 simplifies to 1089/100 by dividing both terms by their greatest common divisor, 1. Its decimal value is 10.89. Because the numerator exceeds the denominator, this value is greater than one.

The greatest common divisor of 1089 and 12 is 3. Their least common multiple is 4356. The identity GCD × LCM = 1089 × 12 = 13068 checks both results.

Work through GCF and LCM

Questions about 1089

What are the factors of 1089?

The positive factors are 1, 3, 9, 11, 33, 99, 121, 363, 1089. There are 9 factors, including 1 and 1089.

Is 1089 a prime number?

No. 1089 is composite: 3^2 × 11^2 = 1089.

How do you write 1089 in Roman numerals?

1089 is MLXXXIX in standard subtractive Roman numeral notation.

What is the binary representation of 1089?

1089 in decimal is 10001000001 in base 2. Adding its active place values gives 1024 + 64 + 1 = 1089.

Methods and reference definitions

Number JD calculates each result from the integer on this page. Positive factors are enumerated in pairs; repeated division gives the prime factorization; place values verify base conversions. Decimal square roots are rounded to six places when irrational.

Editorial policy · Report a calculation issue

NUMBER JOURNAL / JD

A reflective note on 1089

Meaning varies by tradition and personal experience. One sighting is not evidence of what will happen next.

The digits of 1089 add to 18. That arithmetic result is separate from the cultural symbolism of the pattern. If this number matters to you, write down what you noticed and choose one grounded action rather than treating the sighting as a prediction.