JavaScript (Node.js), 21 bytes

-1 thanks to @l4m2

The only (decimal) digit used in the source is 0.

_=>-~(-~0n>>~0xFFFFn)

Try it online!

This computes \$1+2^{1+65535}\$

With all the suffixes for BigInts, a direct port of ovs' answer would be 25 bytes:

_=>-~(2n**2n**2n**2n**2n)

Try it online!

JavaScript (Node.js), 21 bytes

-1 thanks to @l4m2

The only (decimal) digit used in the source is 0.

_=>-~(-~0n>>~0xFFFFn)

Try it online!

This computes \$1+2^{1+65535}\$

With all the BigInt suffixes and extra parentheses due to a different operator precedence, a direct port of ovs' answer would be 25 bytes:

_=>-~(2n**2n**2n**2n**2n)

Try it online!

JavaScript (Node.js), 21 bytes

-1 thanks to @l4m2

The only digit used in the source is 0.

_=>-~(-~0n>>~0xFFFFn)

Try it online!

A direct port of ovs' answer would be 25 bytes:

_=>-~(2n**2n**2n**2n**2n)

Try it online!

JavaScript (Node.js), 21 bytes

-1 thanks to @l4m2

The only (decimal) digit used in the source is 0.

_=>-~(-~0n>>~0xFFFFn)

Try it online!

This computes \$1+2^{1+65535}\$

With all the suffixes for BigInts, a direct port of ovs' answer would be 25 bytes:

_=>-~(2n**2n**2n**2n**2n)

Try it online!

JavaScript (Node.js), 22 bytes

The only digit used in the source is 0.

_=>-~(-~0n<<-~0xFFFFn)

Try it online!

A direct port of ovs' answer would be 25 bytes:

_=>-~(2n**2n**2n**2n**2n)

Try it online!

JavaScript (Node.js), 21 bytes

-1 thanks to @l4m2

The only digit used in the source is 0.

_=>-~(-~0n>>~0xFFFFn)

Try it online!

A direct port of ovs' answer would be 25 bytes:

_=>-~(2n**2n**2n**2n**2n)

Try it online!