Refers to a small, indefinite number of people, typically more than two or three but not many. Used as a noun, often with a counter or in a noun phrase.
A few of us went on a trip together.
Several people were absent from the meeting.
A few students asked questions.
The students were divided into groups of a few each.
Only a few people came to the meeting.
There were only about a few participants.
数名 means the same 'a few people' as 数人 but sounds more formal, often used in written notices or business contexts.
数人 is a slightly more formal or written way to say 'several people', while 何人か is neutral and common in everyday speech.
数人 refers to just a few people, while 大勢 describes a large crowd or great number of people.
数人 (すうにん) states 'several people', while 何人 (なんにん), which looks almost identical in writing, is the question word 'how many people'.
multiple people; several people; more than one person
Compound of 数 (すう, 'several') and 人 (にん, counter for people). The reading すうにん follows standard on'yomi.