hexakosioihexekontahexaphobia

This is known as hexakosioihexekontahexaphobia.

Some versions catered to hexakosioihexekontahexaphobia by conveying the rumor that his name contains exactly 666 letters, which has not been supported by any reliable spelling.

Another example of hexakosioihexekontahexaphobia comes from the Dutch Christian organisation Stichting Opwekking ("Revival Foundation").