16 divisors

Are Fibonacci Numbers Prime? No. of known terms 51 Largest known term F3340367 OEIS index A001605 Indices of prime Fibonacci numbers Are Fibonacci numbers relatively prime? Definition Two numbers x and y are relatively prime if gcd(x,y) = 1. An interesting fact: Theorem Consecutive Fibonacci numbers are relatively prime. 1,1,2,3,5,8,13,21,34,55,89,144,233,377,… Is F 19 a prime