The biggest Presbyterian church is the National Presbyterian Church in Mexico (Iglesia Nacional Presbiteriana de México), which has around 2,500,000 members and associates and 3000 congregations, but there are other small denominations like the Associate Reformed Presbyterian Church in Mexico which was founded in 1875 by the Associate Reformed Church in North America. The Independent Presbyterian Church and the Presbyterian Reformed Church in Mexico, the National Conservative Presbyterian Church in Mexico are existing churches in the Reformed tradition.

Answer this question, if possible (if impossible, reply "unanswerable"): How many members are in the National Presbyterian Church in Mexico?
2,500,000