Hi My Ht Is 5''7 Age 30 Male, Inside Of

hi my ht is 5''7 age 30 male, inside of my thighs the portion just beside where scrotum touches onboth side turned black in patches and dry what it must be? on the glans penis there is whitish soft material deposition which get wipe on cleaning with water but it recurs after 4-5 hours what it may be what is treatment for it???