10877581

This number is a composite.

10877581 = 11 x 13 x 29 x 43 x 61 is the first 5-brilliant Carmichael number. The sum of its prime factors is the prime 157. It is the concatenation of two semiprimes (10877 and 581); truncates to the prime 1087; has the digital sum 37 (another 2-digit prime like its prime factors); and shares the prime factor 11 with its reversal. Note also that 10877581 = 3246^2 + 584^2 + 3^2, and 3246 + 584 + 3 = 3833, which is prime. [Carmichael]