Factor Calculator

Find all factors and factor pairs of any positive integer.

A factor calculator finds all divisors of a positive integer, displays factor pairs, identifies prime factors, and classifies the number as perfect, abundant, or deficient.

Enter a positive integer. The calculator will find all factors (divisors), show factor pairs, identify prime factors, and classify the number as perfect, abundant, or deficient.

Examples

60

Factors: 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60 (12 factors)

Perfect number

28: factors 1, 2, 4, 7, 14, 28. Sum of proper divisors = 1+2+4+7+14 = 28 (perfect!)

Prime

17: factors are only 1 and 17 (2 factors)

Frequently Asked Questions

What is a factor?
A factor (or divisor) of a number n is any integer that divides n exactly, with no remainder. For example, factors of 12 are 1, 2, 3, 4, 6, and 12.
What is a perfect number?
A perfect number equals the sum of its proper divisors (all factors except itself). The first few are 6, 28, 496, and 8128.
What are abundant and deficient numbers?
Abundant: sum of proper divisors > number (e.g., 12). Deficient: sum of proper divisors < number (e.g., 8). Most numbers are deficient.
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Quick Tips

  • Double-check your inputs — small errors lead to incorrect results.
  • Use factor pairs to quickly verify that all divisors have been found.
  • Check the number classification (perfect, abundant, deficient) for number theory exercises.

A factor calculator finds all divisors of a positive integer, displays factor pairs, identifies prime factors, and classifies the number as perfect, abundant, or deficient.

How to Use This Calculator

Enter a positive integer. The calculator will find all factors (divisors), show factor pairs, identify prime factors, and classify the number as perfect, abundant, or deficient.

Understanding the Formula

A factor of n is any integer that divides n with no remainder. Factor pairs (a, b) satisfy a × b = n. A number is perfect if the sum of its proper divisors equals itself.

Examples

60

Factors: 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60 (12 factors)

Perfect number

28: factors 1, 2, 4, 7, 14, 28. Sum of proper divisors = 1+2+4+7+14 = 28 (perfect!)

Prime

17: factors are only 1 and 17 (2 factors)

Frequently Asked Questions

What is a factor?

A factor (or divisor) of a number n is any integer that divides n exactly, with no remainder. For example, factors of 12 are 1, 2, 3, 4, 6, and 12.

What is a perfect number?

A perfect number equals the sum of its proper divisors (all factors except itself). The first few are 6, 28, 496, and 8128.

What are abundant and deficient numbers?

Abundant: sum of proper divisors > number (e.g., 12). Deficient: sum of proper divisors < number (e.g., 8). Most numbers are deficient.

Assumptions & Limitations

  • Assumes positive integer input.
  • Assumes exact input values; rounding in inputs propagates to results.
  • Performance may degrade for very large numbers approaching the upper input limit.