Country Code: +674
International Call Prefix: 00
Contents
National Significant Numbers (NSN): seven-digits
Format: +674 yyy xxxx
Mobile telephones
5596085
Special Numbers
August 2011: Criden Appi, Director of Telecommunications (Regulatory), Nauru advises "only 556xxxx, 557xxxx, 558xxxx are in use for mobiles and there are no landlines in service".
References
Telephone numbers in Nauru Wikipedia(Text) CC BY-SA