What's the ERP invoice ID character limit?

QBO invoice ID character limit is 21 characters

When pushing invoices from Tabs to Quickbooks (QBO), the invoice ID has a 21 character limit. Invoice IDs longer than 21 characters will cause the invoice send to fail, and you will need to shorten the invoice ID in order to successfully send.

Netsuite invoice ID does not have a character limit

For Netsuite, there is no invoice ID character limit.