# Lucky Number 2013

Here's your nightly math! Just 5 quick minutes of number fun for kids and parents at home. Read a cool fun fact, followed by math riddles at different levels so everyone can jump in. Your kids will love you for it.

# Lucky Number 2013

January 11, 2013

The year 2013 may have looked unlucky with that 13 on the end, but it turned out to be a great number.  It was the first year in a long time with 4 different digits. Also, the number 13 is prime, meaning it’s divisible only by itself and 1, and can’t be split into other equal-sized groups, so 2013 looks kind of yucky and prime also. But you can actually divide a lot of numbers into it.  Let’s do the math to find them!

Wee ones: Of the digits 2, 0, 1 and 3, which one is biggest?

Little kids: Numbers whose digits add up to a multiple of 3 are divisible by 3 (you can add 3 over and over to get that total). What do 2013’s digits add up to, and is it divisible by 3?  Bonus: How old were you in 2013, if you’d already been born?

Big kids: We hadn’t had a year with 4 different digits in a long time. When was the last one before that?  Bonus: Years with 4 different digits are actually pretty common.  Before 1987, what was the last year that repeated any digits?