Yfiros is equal to \(2^{512}\). The term was coined by Oganso.[1] It is also equal to ³4 or to-the-third-four equivalent to \(4^{4^4}\) or \(4^{256}\), in which the superscript 3 represents tetration.
Its full decimal expansion is:
13,407,807,929,942,597,099,574,024,998,205,846,127,479,365,820,592,393,377,723,561,443,721,764,030,073,546,976,801,874,298,166,903,427,690,031,858,186,486,050,853,753,882,811,946,569,946,433,649,006,084,096
Ruble calls it Freerlong as it's the third -long.[2]
Sources[]
- ↑ binary googology stage 1[dead link] (retrieved 2024-12-09)
- ↑ List of the -long suffix numbers. retrieved November 3, 2025
1-15: Long · Overlong · Tooerlong · Freerlong · Forerlong · Foreroverlong · Forertooerlong · Forerfreerlong · Tooerforerlong · Tooerforeroverlong · Tooerforertooerlong · Tooerforerfreerlong · Freerforerlong · Freerforeroverlong · Freerforertooerlong · Freerforerfreerlong
16-31: Hexer- ( -over- · -tooer- · -freer- · -forer- · -forerover- · -forertooer- · -forerfreer- · -tooerforer- · -tooerforerover- · -tooerforertooer- · -tooerforerfreer- · -freerforer- · -freerforerover- · -freerforertooer- · -freerforerfreer- ) long
32-47: Tooerhexer- ( -over- · -tooer- · -freer- · -forer- · -forerover- · -forertooer- · -forerfreer- · -tooerforer- · -tooerforerover- · -tooerforertooer- · -tooerforerfreer- · -freerforer- · -freerforerover- · -freerforertooer- · -freerforerfreer- ) long
48-63: Freerhexer- ( -over- · -tooer- · -freer- · -forer- · -forerover- · -forertooer- · -forerfreer- · -tooerforer- · -tooerforerover- · -tooerforertooer- · -tooerforerfreer- · -freerforer- · -freerforerover- · -freerforertooer- · -freerforerfreer- ) long
64-79: Forerhexer- ( -over- · -tooer- · -freer- · -forer- · -forerover- · -forertooer- · -forerfreer- · -tooerforer- · -tooerforerover- · -tooerforertooer- · -tooerforerfreer- · -freerforer- · -freerforerover- · -freerforertooer- · -freerforerfreer- ) long
80-95: Foreroverhexer- ( -over- · -tooer- · -freer- · -forer- · -forerover- · -forertooer- · -forerfreer- · -tooerforer- · -tooerforerover- · -tooerforertooer- · -tooerforerfreer- · -freerforer- · -freerforerover- · -freerforertooer- · -freerforerfreer- ) long
96-111: Forertooerhexer- ( -over- · -tooer- · -freer- · -forer- · -forerover- · -forertooer- · -forerfreer- · -tooerforer- · -tooerforerover- · -tooerforertooer- · -tooerforerfreer- · -freerforer- · -freerforerover- · -freerforertooer- · -freerforerfreer- ) long
112-127: Forerfreerhexer- ( -over- · -tooer- · -freer- · -forer- · -forerover- · -forertooer- · -forerfreer- · -tooerforer- · -tooerforerover- · -tooerforertooer- · -tooerforerfreer- · -freerforer- · -freerforerover- · -freerforertooer- · -freerforerfreer- ) long
128-143: Tooerforerhexer- ( -over- · -tooer- · -freer- · -forer- · -forerover- · -forertooer- · -forerfreer- · -tooerforer- · -tooerforerover- · -tooerforertooer- · -tooerforerfreer- · -freerforer- · -freerforerover- · -freerforertooer- · -freerforerfreer- ) long
144-159: Tooerforeroverhexer- ( -over- · -tooer- · -freer- · -forer- · -forerover- · -forertooer- · -forerfreer- · -tooerforer- · -tooerforerover- · -tooerforertooer- · -tooerforerfreer- · -freerforer- · -freerforerover- · -freerforertooer- · -freerforerfreer- ) long
160-175: Tooerforertooerhexer- ( -over- · -tooer- · -freer- · -forer- · -forerover- · -forertooer- · -forerfreer- · -tooerforer- · -tooerforerover- · -tooerforertooer- · -tooerforerfreer- · -freerforer- · -freerforerover- · -freerforertooer- · -freerforerfreer- ) long
176-191: Tooerforerfreerhexer- ( -over- · -tooer- · -freer- · -forer- · -forerover- · -forertooer- · -forerfreer- · -tooerforer- · -tooerforerover- · -tooerforertooer- · -tooerforerfreer- · -freerforer- · -freerforerover- · -freerforertooer- · -freerforerfreer- ) long
192-207: Freerforerhexer- ( -over- · -tooer- · -freer- · -forer- · -forerover- · -forertooer- · -forerfreer- · -tooerforer- · -tooerforerover- · -tooerforertooer- · -tooerforerfreer- · -freerforer- · -freerforerover- · -freerforertooer- · -freerforerfreer- ) long
208-223: Freerforeroverhexer- ( -over- · -tooer- · -freer- · -forer- · -forerover- · -forertooer- · -forerfreer- · -tooerforer- · -tooerforerover- · -tooerforertooer- · -tooerforerfreer- · -freerforer- · -freerforerover- · -freerforertooer- · -freerforerfreer- ) long
224-239: Freerforertooerhexer- ( -over- · -tooer- · -freer- · -forer- · -forerover- · -forertooer- · -forerfreer- · -tooerforer- · -tooerforerover- · -tooerforertooer- · -tooerforerfreer- · -freerforer- · -freerforerover- · -freerforertooer- · -freerforerfreer- ) long
240-255: Freerforerfreerhexer- ( -over- · -tooer- · -freer- · -forer- · -forerover- · -forertooer- · -forerfreer- · -tooerforer- · -tooerforerover- · -tooerforertooer- · -tooerforerfreer- · -freerforer- · -freerforerover- · -freerforertooer- · -freerforerfreer- ) long
256-264:Byterlong, Interlong, Shorterlong, Titlongertotlong