Number dictionary · Exact arithmetic

120: factors and number facts

one hundred twenty is an even number and is composite. Its 16 positive divisors form 8 factor pairs.

Number JD Editorial Team · Updated 2026-10-08

In words
one hundred twenty
Roman numeral
CXX
Prime factorization
2^3 × 3 × 5
Digital root
3

All factors of 120

A positive factor divides 120 with no remainder. In ascending order, the complete list is:

1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120

Factor pairs

  • 1 × 120 = 120
  • 2 × 60 = 120
  • 3 × 40 = 120
  • 4 × 30 = 120
  • 5 × 24 = 120
  • 6 × 20 = 120
  • 8 × 15 = 120
  • 10 × 12 = 120

Each pair describes an arrangement of 120 items into equal rows. The pairs have different row and column counts; 120 cannot make a square array of whole items.

Divisor totals

Positive divisors
16
Sum of all divisors
360
Sum excluding 120
240
Classification
abundant

120 is abundant because its proper divisors add to 240, which is greater than 120.

Understand factors and multiples

Prime factorization of 120

120 = 2^3 × 3 × 5

Repeated division, step by step

  1. 120 ÷ 2 = 60
  2. 60 ÷ 2 = 30
  3. 30 ÷ 2 = 15
  4. 15 ÷ 3 = 5
  5. 5 ÷ 5 = 1

Multiply the prime divisors in these steps to reconstruct 120. An exponent records how many times the same prime occurs. The divisor-count calculation is (3 + 1) × (1 + 1) × (1 + 1) = 16.

The preceding prime is 113. The next larger prime is 127. The factor list above explains why 120 is composite.

Learn the factorization method

120 in words, Roman numerals and other bases

Equivalent representations of the integer 120
RepresentationValue
English (US style)one hundred twenty
Roman numeralCXX
Binary (base 2)1111000
Octal (base 8)170
Decimal (base 10)120
Hexadecimal (base 16)78

Check the binary conversion

Read 1111000 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 + 16 + 8 = 120

Check the hexadecimal conversion

7 × 16^1 + 8 × 16^0 = 120

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 120

120 squared
120 × 120 = 14,400
120 cubed
120 × 120 × 120 = 1,728,000
Square root
≈ 10.954451
Simplified radical
2√30

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

120 is triangular: it is the sum of the integers from 1 through 15.

Distinguish a square from a square root

Multiplication table for 120

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

120 × 1120
120 × 2240
120 × 3360
120 × 4480
120 × 5600
120 × 6720
120 × 7840
120 × 8960
120 × 91,080
120 × 101,200
120 × 111,320
120 × 121,440

Divisibility checks

Quotients and remainders for divisors 2 through 12
Divide byWhole quotientRemainderDivides exactly?
2600Yes
3400Yes
4300Yes
5240Yes
6200Yes
7171No
8150Yes
9133No
10120Yes
111010No
12100Yes

For example, 120 = 7 × 17 + 1. A remainder of zero is what makes a divisor a factor.

Digit sum and digital root of 120

120 contains 3 decimal digits. Its digit sum is 1 + 2 + 0 = 3.

  1. 120: 1 + 2 + 0 = 3

The digital root is 3. Reversing its digits gives 021; 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, 120/100 simplifies to 6/5 by dividing both terms by their greatest common divisor, 20. Its decimal value is 1.2. Because the numerator exceeds the denominator, this value is greater than one.

The greatest common divisor of 120 and 12 is 12. Their least common multiple is 120. The identity GCD × LCM = 120 × 12 = 1440 checks both results.

Work through GCF and LCM

Questions about 120

What are the factors of 120?

The positive factors are 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120. There are 16 factors, including 1 and 120.

Is 120 a prime number?

No. 120 is composite: 2^3 × 3 × 5 = 120.

How do you write 120 in Roman numerals?

120 is CXX in standard subtractive Roman numeral notation.

What is the binary representation of 120?

120 in decimal is 1111000 in base 2. Adding its active place values gives 64 + 32 + 16 + 8 = 120.

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 120

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

The digits of 120 add to 3. 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.