XPath Syntax if we have multiple Namespaces in ProcessData

Reading the XPath if we have multiple namespaces in ProcessData,

ProcessData

<ProcessData>
<RevealPanReply xmlns="http://w3schools.com/account/services/1.0/">
        <MessageHeader>
            <payment:CreateTimestamp xmlns:payment="http://w3schools.com/account/types/1.0/">2013-01-18T17:58:31.204Z</payment:CreateTimestamp>
        </MessageHeader>
        <PaymentAccountNumber>4111111111111111</PaymentAccountNumber>
</RevealPanReply>
</ProcessData>

XPath

/ProcessData//*[local-name()='PaymentAccountNumber']