Number dictionary · Exact arithmetic

789: factors and number facts

seven hundred eighty-nine is an odd number and is composite. Its 4 positive divisors form 2 factor pairs.

Number JD Editorial Team · Updated 2026-10-08

In words
seven hundred eighty-nine
Roman numeral
DCCLXXXIX
Prime factorization
3 × 263
Digital root
6

All factors of 789

A positive factor divides 789 with no remainder. In ascending order, the complete list is:

1, 3, 263, 789

Factor pairs

  • 1 × 789 = 789
  • 3 × 263 = 789

Each pair describes an arrangement of 789 items into equal rows. The pairs have different row and column counts; 789 cannot make a square array of whole items.

Divisor totals

Positive divisors
4
Sum of all divisors
1056
Sum excluding 789
267
Classification
deficient

789 is deficient because its proper divisors add to 267, which is less than 789.

Understand factors and multiples

Prime factorization of 789

789 = 3 × 263

Repeated division, step by step

  1. 789 ÷ 3 = 263
  2. 263 ÷ 263 = 1

Multiply the prime divisors in these steps to reconstruct 789. Each prime in this factorization occurs once. The divisor-count calculation is (1 + 1) × (1 + 1) = 4.

The preceding prime is 787. The next larger prime is 797. The factor list above explains why 789 is composite.

Learn the factorization method

789 in words, Roman numerals and other bases

Equivalent representations of the integer 789
RepresentationValue
English (US style)seven hundred eighty-nine
Roman numeralDCCLXXXIX
Binary (base 2)1100010101
Octal (base 8)1425
Decimal (base 10)789
Hexadecimal (base 16)315

Check the binary conversion

Read 1100010101 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 + 16 + 4 + 1 = 789

Check the hexadecimal conversion

3 × 16^2 + 1 × 16^1 + 5 × 16^0 = 789

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 789

789 squared
789 × 789 = 622,521
789 cubed
789 × 789 × 789 = 491,169,069
Square root
≈ 28.089144
Simplified radical
√789

789 lies between 784 (28²) and 841 (29²), so it is not a perfect square. It is not a perfect cube.

789 is not triangular: no positive whole-number k satisfies k(k + 1) / 2 = 789.

Distinguish a square from a square root

Multiplication table for 789

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

789 × 1789
789 × 21,578
789 × 32,367
789 × 43,156
789 × 53,945
789 × 64,734
789 × 75,523
789 × 86,312
789 × 97,101
789 × 107,890
789 × 118,679
789 × 129,468

Divisibility checks

Quotients and remainders for divisors 2 through 12
Divide byWhole quotientRemainderDivides exactly?
23941No
32630Yes
41971No
51574No
61313No
71125No
8985No
9876No
10789No
11718No
12659No

For example, 789 = 7 × 112 + 5. A remainder of zero is what makes a divisor a factor.

Digit sum and digital root of 789

789 contains 3 decimal digits. Its digit sum is 7 + 8 + 9 = 24.

  1. 789: 7 + 8 + 9 = 24
  2. 24: 2 + 4 = 6

The digital root is 6. Reversing its digits gives 987; 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, 789/100 simplifies to 789/100 by dividing both terms by their greatest common divisor, 1. Its decimal value is 7.89. Because the numerator exceeds the denominator, this value is greater than one.

The greatest common divisor of 789 and 12 is 3. Their least common multiple is 3156. The identity GCD × LCM = 789 × 12 = 9468 checks both results.

Work through GCF and LCM

Questions about 789

What are the factors of 789?

The positive factors are 1, 3, 263, 789. There are 4 factors, including 1 and 789.

Is 789 a prime number?

No. 789 is composite: 3 × 263 = 789.

How do you write 789 in Roman numerals?

789 is DCCLXXXIX in standard subtractive Roman numeral notation.

What is the binary representation of 789?

789 in decimal is 1100010101 in base 2. Adding its active place values gives 512 + 256 + 16 + 4 + 1 = 789.

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 789

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

The digits of 789 add to 24. 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.