MATL, 35 bytes
'nTIFBCAAAAA@A@A@A@@A'tfYqwIEW-^X$p
Explanation
This uses the prime factorization of the number:
\$ 808017424794512875886459904961710757005754368000000000 \\ = 2^{46} · 3^{20} · 5^9 · 7^6 · 11^2 · 13^3 · 17 · 19 · 23 · 29 · 31 · 41 · 47 · 59 · 71. \$
'nTIFBCAAAAA@A@A@A@@A' % Push this string
t % Duplicate
f % Indices of all nonzero chars: gives [1 2 3 ... 19 20]
Yq % n-th prime, element-wise: gives [2 3 5 ... 67 71]
w % Swap
IEW % Push 3, multiply by 2, exponential with base 2: gives 64
- % Subtract, element-wise: subtracts 64 from the code point
% of each character of the string. Gives [46 20 9 ... 0 1]
^ % Element-wise power. Gives [2^46 3^20 5^9 ... 1 71]
X$ % Convert to symbolic (to achieve arbitrary precision)
p % Product. Implicit display