Number dictionary · Exact arithmetic

108: factors and number facts

one hundred eight is an even number and is composite. Its 12 positive divisors form 6 factor pairs.

Number JD Editorial Team · Updated 2026-10-08

In words
one hundred eight
Roman numeral
CVIII
Prime factorization
2^2 × 3^3
Digital root
9

All factors of 108

A positive factor divides 108 with no remainder. In ascending order, the complete list is:

1, 2, 3, 4, 6, 9, 12, 18, 27, 36, 54, 108

Factor pairs

  • 1 × 108 = 108
  • 2 × 54 = 108
  • 3 × 36 = 108
  • 4 × 27 = 108
  • 6 × 18 = 108
  • 9 × 12 = 108

Each pair describes an arrangement of 108 items into equal rows. The pairs have different row and column counts; 108 cannot make a square array of whole items.

Divisor totals

Positive divisors
12
Sum of all divisors
280
Sum excluding 108
172
Classification
abundant

108 is abundant because its proper divisors add to 172, which is greater than 108.

Understand factors and multiples

Prime factorization of 108

108 = 2^2 × 3^3

Repeated division, step by step

  1. 108 ÷ 2 = 54
  2. 54 ÷ 2 = 27
  3. 27 ÷ 3 = 9
  4. 9 ÷ 3 = 3
  5. 3 ÷ 3 = 1

Multiply the prime divisors in these steps to reconstruct 108. An exponent records how many times the same prime occurs. The divisor-count calculation is (2 + 1) × (3 + 1) = 12.

The preceding prime is 107. The next larger prime is 109. The factor list above explains why 108 is composite.

Learn the factorization method

108 in words, Roman numerals and other bases

Equivalent representations of the integer 108
RepresentationValue
English (US style)one hundred eight
Roman numeralCVIII
Binary (base 2)1101100
Octal (base 8)154
Decimal (base 10)108
Hexadecimal (base 16)6C

Check the binary conversion

Read 1101100 from right to left using place values 1, 2, 4, 8 and successive powers of two. Keep the values whose bit is 1:

64 + 32 + 8 + 4 = 108

Check the hexadecimal conversion

6 × 16^1 + 12 × 16^0 = 108

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 108

108 squared
108 × 108 = 11,664
108 cubed
108 × 108 × 108 = 1,259,712
Square root
≈ 10.392305
Simplified radical
6√3

108 lies between 100 (10²) and 121 (11²), so it is not a perfect square. It is not a perfect cube.

108 is not triangular: no positive whole-number k satisfies k(k + 1) / 2 = 108.

Distinguish a square from a square root

Multiplication table for 108

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

108 × 1108
108 × 2216
108 × 3324
108 × 4432
108 × 5540
108 × 6648
108 × 7756
108 × 8864
108 × 9972
108 × 101,080
108 × 111,188
108 × 121,296

Divisibility checks

Quotients and remainders for divisors 2 through 12
Divide byWhole quotientRemainderDivides exactly?
2540Yes
3360Yes
4270Yes
5213No
6180Yes
7153No
8134No
9120Yes
10108No
1199No
1290Yes

For example, 108 = 7 × 15 + 3. A remainder of zero is what makes a divisor a factor.

Digit sum and digital root of 108

108 contains 3 decimal digits. Its digit sum is 1 + 0 + 8 = 9.

  1. 108: 1 + 0 + 8 = 9

The digital root is 9. Reversing its digits gives 801; 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, 108/100 simplifies to 27/25 by dividing both terms by their greatest common divisor, 4. Its decimal value is 1.08. Because the numerator exceeds the denominator, this value is greater than one.

The greatest common divisor of 108 and 12 is 12. Their least common multiple is 108. The identity GCD × LCM = 108 × 12 = 1296 checks both results.

Work through GCF and LCM

Questions about 108

What are the factors of 108?

The positive factors are 1, 2, 3, 4, 6, 9, 12, 18, 27, 36, 54, 108. There are 12 factors, including 1 and 108.

Is 108 a prime number?

No. 108 is composite: 2^2 × 3^3 = 108.

How do you write 108 in Roman numerals?

108 is CVIII in standard subtractive Roman numeral notation.

What is the binary representation of 108?

108 in decimal is 1101100 in base 2. Adding its active place values gives 64 + 32 + 8 + 4 = 108.

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 108

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

The digits of 108 add to 9. 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.