Untrecentillion

An untrecentillion is equal to \(10^{906}\) in the short scale and \(10^{1806}\) in the long scale by the and 's naming systemConway and Guy. (1995) "The book of Numbers" Copernicus as it is the 301st -illion number.
In the long scale, \(10^{906}\) is called unquinquagintacentillion.
==Approximations==
For the short scale:
Notation 	Lower bound 	Upper bound
Scientific notation 	\(1\times10^{906}\) (exact) 	\(1\times10^{906}\) (exact)
Arrow notation 	\(10\uparrow 906\) (exact) 	\(10\uparrow 906\) (exact)
Steinhaus-Moser Notation 	355[3] 	356[3]
Chained arrow notation 	\(10\rightarrow 906\) (exact) 	\(10\rightarrow 906\) (exact)
Taro's multivariable Ackermann function	A(3,3006) 	A(3,3007)
BEAF & Bird's array notation 	{10,906} (exact) 	{10,906} (exact)
Hyper-E notation 	E906 (exact) 	E906 (exact)
s(n) map 	\(s(1)^3(\lambda x.x+1)(8)\) 	\(s(1)^3(\lambda x.x+1)(9)\)
m(n) map 	m(1)(355) 	m(1)(356)
Bashicu matrix system 	(0)(0)(0)(0)(0)(0)(0)(0)(0)[58] 	(0)(0)(0)(0)(0)(0)(0)(0)(0)[59]
Fast-growing hierarchy 	\(f_2(2998)\) 	\(f_2(2999)\)
Hardy hierarchy 	\(H_{\omega^2}(2998)\) 	\(H_{\omega^2}(2999)\)
Slow-growing hierarchy 	\(g_{\omega^{\omega^2 9+6}}(10)\) (exact)	\(g_{\omega^{\omega^2 9+6}}(10)\) (exact)
For the long scale:
Notation 	Lower bound 	Upper bound
Scientific notation 	\(1\times10^{1806}\) (exact) 	\(1\times10^{1806}\) (exact)
Arrow notation 	\(10\uparrow 1806\) (exact) 	\(10\uparrow 1806\) (exact)
Steinhaus-Moser Notation 	643[3] 	644[3]
Chained arrow notation 	\(10\rightarrow 1806\) (exact) 	\(10\rightarrow 1806\) (exact)
Taro's multivariable Ackermann function	A(3,5996) 	A(3,5997)
BEAF & Bird's array notation 	{10,1806} (exact) 	{10,1806} (exact)
Hyper-E notation 	E1806 (exact) 	E1806 (exact)
s(n) map 	\(s(1)^3(\lambda x.x+1)(9)\) 	\(s(1)^3(\lambda x.x+1)(10)\)
m(n) map 	m(1)(643) 	m(1)(644)
Bashicu matrix system 	(0)(1)[3] 	(0)(1)[4]
Fast-growing hierarchy 	\(f_2(5986)\) 	\(f_2(5987)\)
Hardy hierarchy 	\(H_{\omega^2}(5986)\) 	\(H_{\omega^2}(5987)\)
Slow-growing hierarchy 	\(g_{\omega^{\omega^3+\omega^2 8+6}}(10)\) (exact)	\(g_{\omega^{\omega^3+\omega^2 8+6}}(10)\) (exact)
== Sources ==
== See also ==
Category:Numbers
Category:Class 2
Category:Illion
Category:Numbers with 101 to 999 digits
Category:Powers of 10 with squarefree exponent
Category:Tier 1 -illion numbers