A sixth unitary number, if discovered, would have at least nine odd prime factors.Five is conjectured to be the only odd untouchable number, and if this is the case then five will be the only odd prime number that is not the base of an aliquot tree.In figurate numbers, 5 is a pentagonal number, with the sequence of pentagonal numbers starting: 1, 5, 12, 22, 35, ...
5 is a centered tetrahedral number: 1, 5, 15, 35, 69, ... Every centered tetrahedral number with an index of 2, 3 or 4 modulo 5 is divisible by 5. 5 is a square pyramidal number: 1, 5, 14, 30, 55, ... The sum of the first four members is 50 while the fifth indexed member in the sequence is 55. 5 is a centered square number: 1, 5, 13, 25, 41, ... The fifth square number or 52 is 25, which features in the proportions of the two smallest (3, 4, 5) and (5, 12, 13) primitive Pythagorean triples.The factorial of five, or 
  
    
      
        5
      
    
    {\displaystyle 5}
  !
Epilepsia partialis continua is a rare type of brain disorder in which a patient experiences recurrent motor epileptic seizures that are focal (hands and face), and recur every few seconds or minutes for extended periods (days to years). It is sometimes called Kozhevnikovs epilepsia named after Russian psychiatrist Aleksei Yakovlevich Kozhevnikov who first described this type of epilepsy. Signs and symptoms
During these seizures, there is repetitive focal myoclonus or Jacksonian march. After a seizure has subsided, Todds phenomenon may be observed, which includes transient unilateral weakness. Causes
There are numerous causes for this kind of seizure and they differ depending somewhat on the age at which the seizures begin. Epilepsy most often occurs at the extremes of life – in childhood or in very old age – but can develop at any time throughout ones life. Although these seizures are usually due to large, acute brain lesions resulting from strokes in adults and focal cortical inflammatory processes in children (Rasmussens encephalitis), possibly caused by chronic viral infections, edema, or autoimmune processes. They are very medication and therapy-resistant, and the primary therapeutic goal is to stop secondary generalization. There are also many other reasons why these seizures occur. For example, they could be due to genetics, infections, or problems with brain development. Commonly the cause is unknown. Genetic background determines such features as height, eye color, and potential to develop certain diseases like diabetes, but it also determines all the chemicals and structures that make up the brain, therefore playing a role in epilepsia partialis continua.