BUILT-IN MATHEMATICA SYMBOL

# FactorInteger

gives a list of the prime factors of the integer n, together with their exponents.

FactorInteger[n, k]
does partial factorization, pulling out at most k distinct factors.

## Details and OptionsDetails and Options

• For negative numbers, the unit is included in the list of factors.
• FactorInteger also works on rational numbers. The prime factors of the denominator are given with negative exponents. »
• The last element in the list FactorInteger[n, k] gives what is left after the partial factorization.
• factors over Gaussian integers. »
• FactorInteger[m+I n] automatically works over the Gaussian integers.
• When necessary, a unit of the form , {I, 1}, or {-I, 1} is included in the list of factors.
• pulls out only factors that are easy to find.
• FactorInteger uses PrimeQ to determine whether factors are prime.

## ExamplesExamplesopen allclose all

### Basic Examples (2)Basic Examples (2)

Find prime factors and their exponents:

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