436 is the number of people recorded as women, charged with rape between 2012-2018 in England and Wales - where the legal definition of rape requires use of a penis. Links and details in this thread
www.mumsnet.com/Talk/womens_rights/4360759-More-than-one-woman-a-week-prosecuted-for-rape
Note charged with rape though, not convicted and sent to prison, so extrapolating to 38 per women’s prison isn’t supported.
Seeing as conviction stats for rape are shamefully around 5% IIRC, it’d be more like around 22 convicted rapists recorded as women in that time, very roughly, I think.