There are a few expressions already:
getbit(x, n)
Get the nth bit of x represented as a 32-bit integer. For example getbit(7, 0) will get the least significant bit of the number 7 when represented as a 32-bit integer. Returns either 0 or 1.
setbit(x, n, b)
Set the nth bit of x represented as a 32-bit integer to b (either 0 or 1). The resulting 32-bit integer is returned.
togglebit(x, n)
Toggle the nth bit of x represented as a 32-bit integer. If that bit is 0, it is set to 1; if it is 1, it is set to 0. The resulting 32-bit integer is returned.
And Yann made a plug: