Those values actually have the computer name e.g.:
30# $r = Invoke-Command ...
31# $r[0]
4
32# $r[0].PSComputerName
hillr2
PowerShell just doesn't display that info by default for number. You could do this:
32# icm hillr2 -ScriptBlock {
>>> $NumLogCpu = (Get-CimInstance Win32_Processor).NumberOfLogicalProcessors
>>> $MemSize = ((Get-CimInstance Win32_PhysicalMemory).Capacity | Measure-Object -Sum).Sum /1GB
>>> [pscustomobject]@{NumLogCpu=$NumLogCpu;MemSize=$MemSize}
>>> }
NumLogCpu : 4
MemSize : 8.00390625
PSComputerName : hillr2
RunspaceId : fb03fedd-2771-46cf-916a-f31ec7c8298b
This requires PowerShell v3 or higher for the [pscustomobject] type accelerator.