Formula to extract numbers from a text string

Question

How could I extract only the numbers from a text string in Excel or Google Sheets? For example:

A1 - a1b23eg67
A2 - 15dgrgr156

Result desir

Answer 1

Because you asked for Excel also,

If you have a subscription to office 365 Excel then you can use this array formula:

=--TEXTJOIN("",TRUE,IF(ISNUMBER(--MID(A1,ROW(INDIRECT("1:"&LEN(A1))),1)),MID(A1,ROW(INDIRECT("1:"&LEN(A1))),1),""))

Being an array formula it needs to be confirmed with Ctrl-Shift-Enter instead of Enter when exiting edit mode. If done correctly then Excel will put {} around the formula.