Stars vary widely in size, mass, brightness, and longevity. The largest are about 100 times the mass of the Sun and about 10 times the Sun’s diameter (while on the main sequence, but later swelling by a factor of 100 as red supergiants). They give off almost a million times as much light as the Sun. These large stars burn their fuel so rapidly that they can exist on the main sequence less than 
as long as the Sun. The Sun will remain on the main sequence for an estimated 10 billion years, becoming a white dwarf about a billion years later. The smallest stars, barely able to carry out nuclear fusion in their cores, are roughly 
the Sun’s mass, its diameter, and as bright, but they will shine for trillions of years.
The Sun is in some sense an ordinary, midsize, middle-aged star, but its ranking depends on the group of comparison stars. Compared to the stars one sees in the night sky, it is actually quite small and dim. However, one naturally tends to see only the bigger, brighter stars. Comparing the Sun to all the stars (including the ones too dim to see without a telescope), one finds that it is bigger and brighter than about 95 percent of them.
Considering the Sun in the context of the galaxies provides another point of reference. The Sun is only one member out of more than 100 billion stars in the Milky Way galaxy, and this galaxy is of course not the only such group of stars. Billions of galaxies, some containing up to a trillion stars, are scattered across the observable universe, at distances out to at least 12 billion light-years.
Regardless of how the Sun ranks, however, its relatively steady, bright light, lasting for billions of years, is ideal for life on Earth. Most stars would not make good substitutes.