The sum of all minimal primes in base 5 is prime. [Rupinski]
4621 is the (4*6*2*1*(4+6+2+1))th prime. Note that 4621 is the smallest such prime. [Firoozbakht]
The larger prime factor of the (conjectured) smallest Sierpinski number (78557). Ironically, the previous prime (4603) is the larger prime factor of the second composite Sierpinski number (271577).
(There is one curio for this number that has not yet been approved by an editor.)