Get-Factor and Test-Prime functions that are fairly fast, for Powershell

Test-Prime.ps1

function Get-Factor {
    param (
        [Parameter(Mandatory = $true,
            Position = 0,
            ValueFromPipeline = $true)]
        [ValidateNotNullOrEmpty()]
        [int64[]]
        $Number,
        [switch]
        $Prime
    )
    Process {
        $FactorCount = 0
        foreach ($num in $Number) {
            for ($x = 1; $x -le $num; $x++) {
                if ($Prime -and $FactorCount -gt 2) {
                    break
                }
                if ($num % $x -eq 0) {
                    $x
                    $FactorCount++
                }
            }
        }
    }

}

Function Test-Prime {
    param(
        [Parameter(Mandatory = $true,
            Position = 0,
            ValueFromPipeline = $true)]
        [ValidateNotNullOrEmpty()]
        [int64[]]
        $Number
    )
    Process {
        if ($($Number | Get-Factor -Prime).Count -le 2) {
            $Number
        }
    }
}

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