987

987 = 3 x 7 x 47.

987 is the 16th Fibonacci number.

987 is a divisor of 46⁶ - 1.

987 is the only three-digit number with consecutively decreasing digits such that when multiplied by the sum of its digits plus and minus 1, the results are primes: 987(9 + 8 + 7) - 1 = 23,687 and 987(9 + 8 + 7) + 1 = 23,689.

1 x 8 + 1 = 9

12 x 8 + 2 = 98

123 x 8 + 3 = 987

1234 x 8 + 4 = 9876

12345 x 8 + 5 = 98765

987 Hotels has hotels in Prague and Barcelona.

Source: Prime Curios!