biggest integer that can be stored in a double

Question

What is the biggest \"no-floating\" integer that can be stored in an IEEE 754 double type without losing precision ?

Answer 1

You need to look at the size of the mantissa. An IEEE 754 64 bit floating point number (which has 52 bits, plus 1 implied) can exactly represent integers with an absolute value of less than or equal to 2^53.