Number dictionary · Exact arithmetic

1009: factors and number facts

one thousand nine is an odd number and is prime. Its 2 positive divisors form 1 factor pair.

Number JD Editorial Team · Updated 2026-10-08

In words
one thousand nine
Roman numeral
MIX
Prime factorization
1009
Digital root
1

All factors of 1009

A positive factor divides 1009 with no remainder. In ascending order, the complete list is:

1, 1009

Factor pairs

  • 1 × 1009 = 1009

Each pair describes an arrangement of 1009 items into equal rows. The pairs have different row and column counts; 1009 cannot make a square array of whole items.

Divisor totals

Positive divisors
2
Sum of all divisors
1010
Sum excluding 1009
1
Classification
deficient

1009 is deficient because its proper divisors add to 1, which is less than 1009.

Understand factors and multiples

Prime factorization of 1009

1009 = 1009

Repeated division, step by step

  1. 1009 ÷ 1009 = 1

Multiply the prime divisors in these steps to reconstruct 1009. Each prime in this factorization occurs once. The divisor-count calculation is (1 + 1) = 2.

The preceding prime is 997. The next larger prime is 1013. To check 1009 for primality, it is sufficient to test possible divisors from 2 through 31.

Learn the factorization method

1009 in words, Roman numerals and other bases

Equivalent representations of the integer 1009
RepresentationValue
English (US style)one thousand nine
Roman numeralMIX
Binary (base 2)1111110001
Octal (base 8)1761
Decimal (base 10)1009
Hexadecimal (base 16)3F1

Check the binary conversion

Read 1111110001 from right to left using place values 1, 2, 4, 8 and successive powers of two. Keep the values whose bit is 1:

512 + 256 + 128 + 64 + 32 + 16 + 1 = 1009

Check the hexadecimal conversion

3 × 16^2 + 15 × 16^1 + 1 × 16^0 = 1009

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 1009

1009 squared
1009 × 1009 = 1,018,081
1009 cubed
1009 × 1009 × 1009 = 1,027,243,729
Square root
≈ 31.764760
Simplified radical
√1009

1009 lies between 961 (31²) and 1024 (32²), so it is not a perfect square. It is not a perfect cube.

1009 is not triangular: no positive whole-number k satisfies k(k + 1) / 2 = 1009.

Distinguish a square from a square root

Multiplication table for 1009

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

1009 × 11,009
1009 × 22,018
1009 × 33,027
1009 × 44,036
1009 × 55,045
1009 × 66,054
1009 × 77,063
1009 × 88,072
1009 × 99,081
1009 × 1010,090
1009 × 1111,099
1009 × 1212,108

Divisibility checks

Quotients and remainders for divisors 2 through 12
Divide byWhole quotientRemainderDivides exactly?
25041No
33361No
42521No
52014No
61681No
71441No
81261No
91121No
101009No
11918No
12841No

For example, 1009 = 7 × 144 + 1. A remainder of zero is what makes a divisor a factor.

Digit sum and digital root of 1009

1009 contains 4 decimal digits. Its digit sum is 1 + 0 + 0 + 9 = 10.

  1. 1009: 1 + 0 + 0 + 9 = 10
  2. 10: 1 + 0 = 1

The digital root is 1. Reversing its digits gives 9001; 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, 1009/100 simplifies to 1009/100 by dividing both terms by their greatest common divisor, 1. Its decimal value is 10.09. Because the numerator exceeds the denominator, this value is greater than one.

The greatest common divisor of 1009 and 12 is 1. Their least common multiple is 12108. The identity GCD × LCM = 1009 × 12 = 12108 checks both results.

Work through GCF and LCM

Questions about 1009

What are the factors of 1009?

The positive factors are 1, 1009. There are 2 factors, including 1 and 1009.

Is 1009 a prime number?

Yes. The only positive divisors of 1009 are 1 and 1009.

How do you write 1009 in Roman numerals?

1009 is MIX in standard subtractive Roman numeral notation.

What is the binary representation of 1009?

1009 in decimal is 1111110001 in base 2. Adding its active place values gives 512 + 256 + 128 + 64 + 32 + 16 + 1 = 1009.

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.

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A reflective note on 1009

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

The digits of 1009 add to 10. 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.