What number should come in place of the question mark below?

I am thinking of a five-digit number such that:
The first and last digits are the same, their submission is an even number and multiplication is an odd number and is equal to the fourth number. Subtract five from it and we obtain the second number. Then divide into exact halves and we get the 3rd number.

What number I am thinking of?

Find a 9-digit number, which you will gradually round off starting with units, then tenth, hundred etc., until you get to the last numeral, which you do not round off. The rounding alternates (up, down, up ...). After rounding off 8 times, the final number is 500000000. The original number is commensurable by 6 and 7, all the numbers from 1 to 9 are used, and after rounding four times the sum of the not-rounded numerals equals 24.

Why did Navjot Singh Sidhu put the new January calendar in the freezer

What word begins and ends with an E, but has only one letter?

A man looks at a painting in a museum and says, “Brothers and sisters I have none, but that man’s father is my father’s son.” Who is in the painting?

I know a ten-letter word in the English language which can be typed using only the top rows of the computer keyboard.

Find the next number in the series.
1 10 24 43 67 ?

There was an aeroplane crash, every single person died, but two people survived. How is this possible?

Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?