check digit
Assuming that you mean a digit, it is a terminating decimal.
There is no THE 80 digit number - there are 9*1079 of them and each one of them has a differen name just as 11 and 12, both 2-digit numbers, have different names.
1234567890
Tenths
1200000000000000000$
one two gazillions
it has 1200000000000000000 babies a week. tmd
check digit
Assuming that you mean a digit, it is a terminating decimal.
What is 36 single digit number
digit
There is no THE 80 digit number - there are 9*1079 of them and each one of them has a differen name just as 11 and 12, both 2-digit numbers, have different names.
A 24-digit number is called a septillion, as it consists of 24 individual numerical digits. In the context of computing, a 24-digit number can also be referred to as a "double precision" floating-point number, typically used to represent very large or very small values with high precision. In mathematics, a 24-digit number can be used to express extremely large quantities or precise measurements.
Count off the eleventh digit from the right.
Just that - a 26-digit number. There is no special name for that.
Such numbers are best written - and pronounced - in scientific notation. Normally you don't need all the digits, so you can round such a number to an appropriate number of significant digits - for example, 25670000..... Then you express it in scientific notation, in this example, 2.567 x 1025. Edit: I agree entirely with the previous answer but, if you must: The 2-digit name for digits 1-2 followed by "septillion", the 3-digit name for digits 3-5 followed by "sextillion", the 3-digit name for digits 6-8 followed by "quintillion", the 3-digit name for digits 9-11 followed by "quadrillion", the 3-digit name for digits 12-14 followed by "trillion", the 3-digit name for digits 15-17 followed by "billion", the 3-digit name for digits 18-20 followed by "million", the 3-digit name for digits 21-23 followed by "thousand", and the 3-digit name for digits 24-26.