2^64

2^64=18,446,744,073,709,551,616

2^64 is also 4^32, 16^16, 256^8, 65536^4, and 4,294,967,296^2. 

The factors of 2^64 are the first 63 powers of 2. 

2^64 is also called Fzsixteen because it is 16^16. 

Other ways to write 2^64 are 

2↑64, 4↑32, 16↑16, 256↑8, 65536↑4, and 4294967296↑2 in Knuth's Arrow notation. 

{2,64}, {4,32}, {16,16} , {256.8}, {65536,4}, and {4294967296,2} in BEAF and Chris Bird's Array Notion

This video explains how 2^64 looks like, well 2^64-1.