387

387 is a natural number that follows 386 and precedes 388. In mathematics, it is an odd composite number with prime factorization 3^2 × 43. It is divisible by 3 and by 9, since the sum of its digits (3 + 8 + 7) equals 18, but it is not divisible by 18, so 387 is not a Harshad (Niven) number. In Roman numerals, 387 is written as CCCLXXXVII. In binary, 387 is 110000011.

In other uses, the international telephone dialing code +387 is assigned to Bosnia and Herzegovina. This code is used when making international calls to the country.

387 Aquitania is a large asteroid in the main asteroid belt. It was discovered in 1894 by Auguste Charlois and is named after the historical region of Aquitaine in southwestern France. As a main-belt object, it orbits the Sun along with many other asteroids, and it is among the larger bodies in that region.

Overall, 387 is most commonly encountered as a three-digit composite number in mathematical contexts, as a country code in telecommunications, and as the designation of a main-belt asteroid.