Dracula did not speak with Vampire Vords in the original book—in fact, the story even makes it clear he speaks fluent English. The accent would come from later adaptations of the story and parodies of it. And in the original book, Dracula never once said "I vant to suck your blood!" and he wouldn't have been caught undead saying "Bleh, bleh bleh!" The original Dracula was far too proud a character to speak in such a manner or accent. Part of the reason he invited Jonathan was to practice his English, so he would not stand out as a foreigner when in England.
His vampire girls were never really called "brides" in the story. They're just simply known as "the sisters". The "brides" term came from the 60's movie, The Brides of Dracula, that more or less stuck.
He also never said "I never drink... wine" in the book; that line comes from the 1931 movie. In the novel, Dracula excuses not eating with Jonathan by saying "I have already dined, and I do not sup." In certain dialects, "dinner" is a midday meal, i.e. "lunch," and "supper" is an evening meal. American English tends to use "dinner" and "supper" interchangeably, and the verb form of "supper" is archaic. It's also something of a pun; "to sup" can mean to drink a liquid in small mouthfuls, and the Count, indeed, "does not sup."
Colbert Bump: After decades of being overshadowed by its numerous adaptations, the original book saw a resurgence of popularity with the launch of Dracula Daily in May 2021, which delivered the letters that make up the novel to subscribers in "real time". In particular, the second run in 2022 became wildly popular on Tumblr, with many people posting jokes, memes, and their thoughts about the day's events in the novel in the #Dracula Daily tag.
Defictionalization: There have been several recipes for Robber Steak printed on the Internet; Dracula-themed restaurants around Transylvania even have them on their menus.
Missing Episode: An early chapter of the novel, concerning an unnamed Englishman's (whom most assume to be Jonathan Harker with the serial numbers sanded off) run in with a vampiress in Munich while on his way to Transylvania on business, was removed from the original manuscript by the publisher. Two years after Stoker's death, it was released as the short story "Dracula's Guest".
Science Imitates Art: A species of giant extinct vampire bat, Desmodus draculae, is named after the title character (as the study naming it stated: "the greatest human vampire of folklore").
When Van Helsing realizes that Lucy is anaemic because her blood is being drained by Dracula, he orders that her three suitors give her blood transfusions to save her life. Transfusions were performed during this time period, but blood types had yet to be discovered. Depending on the blood-types of the parties involved, Lucy's transfusions could have been fatal in their own right. In the story, they are only unsuccessful because Dracula keeps preying on her.note It's worth noting that this does not necessarily make it unrealistic: it's possible, though unlikely, that all of Lucy's blood donors could have had blood types compatible with hers by sheer dumb luck, most likely by Lucy being AB positive, the universal recipient. However, the Victorians not knowing blood types is actually part of what makes Lucy's illness scary, which is where this trope comes in, making it frightening to Victorians and modern readers for similar but opposite reasons—then it would've been a risky, cutting-edge procedure that worked or failed seemingly at random, whereas nowadays, it's a normal procedure performed primitively, and everyone (except, critically, the characters) knows exactly why it might fail.
Dracula's appearance is compiled based on Victorian ideas of physiognomy, which hold that criminals are racially degenerate and atavistically regressive. Dracula's features in particular paint him as a thug and sexual deviant. All of these principles have since been thoroughly discredited.
There's been speculation that Stoker was considering doing a novel series starring Van Helsing as a paranormal equivalent to Sherlock Holmes.
Working Title: Originally The Dead Un-dead, which became just The Un-dead, then Count Wampyr, before Stoker happened upon a book of Wallachian history and fell in love with the name "Dracula".
2023 saw the creation of a podcast titled Re: Dracula, a fully casted and voice acted audio version of the book where each episode is a Dracula Daily-style installment released on the day it takes place in canon. The creators outright stated Dracula Daily was their inspiration for the project.