Number Theory Calculator

Prime Factorization Calculator

Enter an integer to find its prime factorization, repeated prime factors, exponential form, prime-number status, and positive divisor count.

Live calculator

Prime factorization inputs

Break an integer into prime factors, exponential form, expanded factor form, primality status, and divisor count.

Prime factorization

2^3 x 3^2 x 5

Absolute value

360

Prime?

No

Divisors

24

Factor count

6

Prime factorization checks

MeasureValueCheck
Expanded factors2 x 2 x 2 x 3 x 3 x 5The integer written as repeated prime factors.
Exponential form2^3 x 3^2 x 5Repeated prime factors grouped with exponents.
Prime number checkNot primeA prime number has exactly two positive divisors: 1 and itself.
Positive divisor count24Multiply each prime exponent plus one to count positive divisors.

Output

Prime Powers

Check

Prime Status

Count

Divisors

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What Can You Create?

Break integers into prime factors

Expanded factor form

Show each repeated prime factor in multiplication order.

Exponent form

Group repeated factors such as 2 x 2 x 2 into 2^3.

Prime and divisor checks

Identify whether the value is prime and count positive divisors from exponents.

Formula

Prime factorization rule used on this page

Every integer greater than 1 can be written as a product of prime numbers, and that product is unique apart from order.

Working formulas

Prime factorization

n = p1^a x p2^b x p3^c ...

Each p is prime and each exponent counts repeated factors.

Divisor count

(a + 1)(b + 1)(c + 1) ...

Add one to each prime exponent and multiply the results.

Symbols

p - prime factor
A whole number greater than 1 whose only positive divisors are 1 and itself.
a, b, c - exponents
Counts of how many times each prime factor appears.
Read the Result

Interpret this calculation before using it

Prime factorization expresses an integer greater than one as a product of primes. The prime product is unique apart from factor order, so exponent form provides a compact identity that can be checked by multiplication. Divisor count follows from the exponents: add one to each exponent and multiply those counts.

Worked example

For 360, repeated division gives 360 = 2^3 x 3^2 x 5. Multiplying 8 x 9 x 5 returns 360. The number of positive divisors is (3 + 1)(2 + 1)(1 + 1) = 24 because a divisor can choose zero through three factors of 2, zero through two factors of 3, and zero or one factor of 5.

Assumptions to keep

  • Input is interpreted as a whole number within the calculator's supported safe range.
  • For a negative integer, factorization applies to its absolute value with a separate factor of -1.
  • The values 0 and 1 do not have ordinary prime factorizations, so they require special result states.

Limits of this result

Trial division is practical for the calculator's bounded educational inputs but is not a general-purpose method for very large cryptographic integers. A factorization result should multiply back to the original magnitude. Use the exponent form for divisor work and the expanded form when tracing individual prime divisions.

Useful next step: GCD and LCM Calculator Compare prime exponents across multiple integers to find their greatest common divisor or least common multiple.

Factual reference:OpenStax Prealgebra 2e
Why Users Love This Tool

Factorization with exponent and divisor checks

Formula steps that can be audited

  • Scientific notation shows coefficient, exponent, engineering notation, and e notation.
  • Prime factorization keeps expanded and exponent forms visible for checking.
  • GCD and LCM outputs include factor rows so common and repeated factors can be inspected.
  • Copy and print controls preserve the exact method labels used on the result cards.

Guardrails for integer and notation work

  • Integer tools restrict inputs to whole numbers and explain special cases such as negative values.
  • LCM calculations return a clear unavailable state if a result would exceed safe integer precision.
  • Scientific notation separates ordinary decimal value, power of ten, and engineering multiples of three.
  • Related links connect each calculator to the formula library and nearby math workflows.
Perfect For

Prime factorization support for number theory

Students

Check notation, factorization, and divisibility work while seeing each formula convention.

Teachers

Create examples for powers of ten, prime factors, common divisors, and common multiples.

Worksheet builders

Print results and method notes for answer keys, examples, and review sheets.

How It Works

How it works in three quick steps.

1

Enter an integer

Use a whole number between negative one billion and one billion.

2

Read expanded factors

Review the repeated prime factors that multiply back to the absolute value.

3

Check exponent form

Use grouped prime powers for divisor counting, GCD, and LCM work.

Download & Print

Save or print factorization results

Copy result summary

Copy the final answer with formula labels into notes, documents, or worksheets.

Print the page

Print inputs, result cards, method tables, FAQs, and related math links.

Audit method tables

Use the supporting rows to verify powers of ten, factor powers, or divisibility logic.

FAQ

Frequently Asked Questions

What is prime factorization?
Prime factorization writes a whole number as a product of prime numbers. For example, 360 equals 2 cubed times 3 squared times 5. Prime factorization is useful because it reveals divisibility structure that is harder to see in the original number.
How are negative integers handled?
The calculator factors the absolute value and adds -1 to the displayed factorization for negative inputs. Prime factors are usually discussed for positive integers, but showing the -1 factor keeps the multiplication statement correct for negative values.
Is 1 a prime number?
No. One is not prime because a prime number must have exactly two positive divisors: 1 and itself. The number 1 has only one positive divisor. The calculator treats 1 and -1 as special cases rather than assigning prime factors to them.
How does factorization help with GCD and LCM?
Prime factorization makes GCD and LCM easier to audit. The GCD uses prime powers shared by all values. The LCM uses the highest required power of every prime that appears. That is why the GCD and LCM calculator includes factor rows.
What does divisor count mean?
The positive divisor count is how many positive integers divide the value evenly. Once a number is written in prime-power form, add one to each exponent and multiply those adjusted values. That works because each divisor chooses an exponent from zero through the prime's maximum exponent.
About This Tool

About this prime factorization calculator

Toolarithm's Prime Factorization Calculator is designed for divisibility work that needs more than a final answer. It shows expanded prime factors, grouped exponent form, whether the input is prime, and the positive divisor count. Negative inputs are handled with a visible -1 factor so the multiplication statement remains accurate.

The calculator supports classroom number theory, fraction reduction, simplifying radicals, GCD and LCM work, and worksheet answer keys. Prime factorization is also a bridge into modular arithmetic, cryptography concepts, and algebraic simplification. Keeping exponent form and divisor count visible makes the output useful for more than a quick lookup.

Editorial Transparency

Who maintains this page

Ownership and review

Written and maintained by the Toolarithm editorial team. No review date is shown without a maintained editorial record. No independent professional review is claimed.

Methodology

Equations are checked by substituting worked examples into the stated relationship and comparing the result with the interactive implementation.

Read the editorial methodology

Dates and sources

Review dates change only after a substantive method or content check.

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