Actinidia five small petals. Most of the species are dioecious with separate male and female plants, but some are monoecious. The fruit is a large berry containing numerous small seeds; in most species, the fruit is edible. In particular, this genus is known for the species "Actinidia deliciosa", the kiwifruit or Chinese gooseberry, and for the hardy ornamental "A. kolomikta". "Actinidia" macrofossils have been recovered from the late Zanclean stage of Pliocene sites in Pocapaglia, Italy. The 40–60 species of "Actinidia" include: Kiwifruit is a cultivar group of "A. deliciosa", and hardy kiwi is the species "Actinidia arguta", which has small
Largest known prime number Largest known prime number The largest known prime number () is 2 − 1, a number with 23,249,425 digits. It was found by the Great Internet Mersenne Prime Search (GIMPS) in 2017. Euclid proved that there is no largest prime number, and many mathematicians and hobbyists continue to search for large prime numbers. Many of the largest known primes are Mersenne primes. , the seven largest known primes are Mersenne primes. The last sixteen record primes were Mersenne primes. The fast Fourier transform implementation of the Lucas–Lehmer primality test for Mersenne numbers is fast compared to other known primality tests