Forty-fours

Forty-fours is equal to \(4 \lfloor 10^{40} / 9\rfloor\), or 40 copies of 4:
:4,444,444,444,444,444,444,444,444,444,444,444,444,444 or hypermathematically with interior superscription as \(4^{38}4\)
:googology
Its prime factorization is 22 × 11 × 41 × 73 × 101 × 137 × 271 × 3,541 × 9,091 × 27,961 × 1,676,321 × 5,964,848,081.
== Approximations ==
Notation 	Lower bound 	Upper bound
Scientific notation 	\(4.444\times10^{39}\) 	\(4.445\times10^{39}\)
Arrow notation 	\(96\uparrow20\) 	\(53\uparrow23\)
Steinhaus-Moser Notation 	27[3] 	28[3]
Copy notation 	4[40] 	4[40]
Taro's multivariable Ackermann function	A(3,128) 	A(3,129)
Pound-Star Notation 	#*(9,8,0,2)*7 	#*(0,5,1,9,10)*5
BEAF 	{96,20} 	{53,23}
Hyper-E notation 	4E39 	5E39
Bashicu matrix system 	(0)(0)(0)[90360] 	(0)(0)(0)[90361]
Hyperfactorial array notation 	34! 	35!
Fast-growing hierarchy 	\(f_2(124)\) 	\(f_2(125)\)
Hardy hierarchy 	\(H_{\omega^2}(124)\) 	\(H_{\omega^2}(125)\)
Slow-growing hierarchy 	\(g_{\omega^{\omega2}13}(16)\)	\(g_{\omega^{\omega6+4}6}(7)\)
== Sources ==
== See also ==
Category:Numbers
Category:Class 2
Category:Even numbers
Category:Numbers by André Joyce
Category:Numbers with 30 to 100 digits
Category:Repdigit numbers