prevPow2 - nodef/extra-bigint GitHub Wiki
Find largest power-of-2 less than or equal to given bigint.
Similar: prevPow2, prevPow10.
Similar: isPow2, prevPow2, nextPow2.
function prevPow2(x)
// x: a bigint
const xbigint = require('extra-bigint');
xbigint.prevPow2(32n);
// → 32n
xbigint.prevPow2(1023n);
// → 512n
References