Huge group - powershell - how to count members

Problem with huge group - members' above 5,000 (web services limit):
(Get-ADGroupMember "some_big_group").Count Get-ADGroupMember : The size limit for this request was exceeded At line:1 char:34 + $groupMembers = Get-ADGroupMember <<<< "some_big_group" + CategoryInfo : NotSpecified: (some_big_group:ADGroup) [Get-ADGrou pMember], ADException + FullyQualifiedErrorId : The size limit for this request was exceeded,Mic rosoft.ActiveDirectory.Management.Commands.GetADGroupMember

Solution:
(Get-ADGroup "some_big_group" -Properties Member | Select -ExpandProperty Member).Count