Is 128 the only multi-digit power of 2 such that each of its digits is also a power of 2?

The number $128$ can be written as $2^n$ with integer $n$, and so can its every individual digit. Is this the only number with this property, apart from the one-digit numbers $1$, $2$, $4$ and $8$?

I have checked a lot, but I don’t know how to prove or disprove it.

Answer

This seems to be an open question. See OEIS sequence A130693 and references there.

Attribution
Source : Link , Question Author : bifurcat , Answer Author : Robert Israel

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