How to check digits of a number

Originally Posted by bebo021999

. . .

=AND(MID(A1,ROW(INDIRECT("2:"&LEN(A1))),1)-MID(A1,ROW(INDIRECT("1:"&LEN(A1)-1)),1)>0)

Would return an error when A1 has just 1 numeral, in which case INDIRECT("1:"&0) would be the cause.