Answer: He could remember up to 70(B) digits or words.
Step-by-step explanation:
Solomon Shereshevsky (1886 – 1958) was a Russian journalist and a subject of multiple neuropsychology studies.
Shereshevsky never took notes during his career, yet the information in his articles was always genuine. His editor thus sent him to a local university for testing.
Alexander Luria, a famous neuropsychologist who studied Solomon's case for thirty years, claimed there was no limit to his memory. When presented with 70-digit matrices, complex formulae, or foreign language texts, Shereshevsky could memorize it all within minutes.