Is it a pleasing number?
APL (Dyalog), 36 bytes



{(⊢≡⌊)(⌈/⍎¨⍵/⍨~o)*÷≢⍵/⍨o←⌽⌊\1,2=/⌽⍵}


Try it online!

How?

Almost a poem.

⌽⍵ - reverse the input once,

1,2=/ - get the differences list.

⌊\ - keep only the first group of ones,

⌽ - and flip it over to complete.



o← - assign to o,

~o - switch ones and zero(s),

⍵/⍨ - filter the input with it,

⍎¨ - turn the result into list of each digit,


⌈/ - and get the maximum. (that's A)




⍵/⍨o - filter the input with o unalt(ered),

≢ - and take the length, that would be B.

÷ - get one divided by this result,

* - and take A to that power thee.



⊢≡⌊ - integer?