tcl, 91 bytes

Result [link]

WA

Code [DL]

set bin [gets stdin]
binary scan [binary format B64 [format "%064s" $bin]] W dec
puts $dec

stdin

1100010010111010000100100010101001111001011011100000010011101001111000000001111101010001011000100001

stdout

-4271081322972314391

stderr

strace