2401

2401 is a number that symbolizes truth in a Crowbar equation. It was discovered in 1995 when Dr. Pilgrim was working on an experimental Fast Universal Recon suit to navigate Xen much faster.

In modern pop culture
Nowadays, When someone says something is "Real 2401", They usually mean that they are completely serious and aren't lying about the situation. People have been sworn into various positions by making them say that they are being "Real 2401" about their promises.