Get Site Collection Admins data using PowerShell

<# Description:

- Extract Primary and Secondary Site Collection Admins in each Site Collection
- Provide root Site Collection URL as the input to this script. It reads the corresponding web application and updates remaining Site Collections using this script
- ',' is used in between each values to separate the data columns in resultant CSV file

#>

$siteUrl = Read-Host "Enter Site URL"
$rootSite = New-Object Microsoft.SharePoint.SPSite($siteUrl)
$spWebApp = $rootSite.WebApplication
foreach($site in $spWebApp.Sites)
 {
        $SiteAdmins = "$($site.Url), $($site.Owner.UserLogin), $($site.SecondaryContact.UserLogin)"
        $SiteAdmins | Out-File "E:\Temp\Site_Collection_Admins\SiteAdmins.csv" -Append

     $site.Dispose()
 }
$rootSite.Dispose()