2020 AMC 8 Problem 17

Attempt Problem 17 of the 2020 AMC 8 below, then check your answer against the video solution and professionally curated solution from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2020 AMC 8 solutions, or check the answer key.

All problems are used with official legal permission of the Mathematical Association of America (MAA).

17.

How many factors of 20202020 have more than 33 factors? (As an example, 1212 has 66 factors, namely 1,1, 2,2, 3,3, 4,4, 6,6, and 12.12.)
66
77
88
99
1010
Answer: B
Concepts:factor countingprime factorization
Small hint:
List or factor the divisors of 20202020
Big hint:
Only 11, primes, and 44 have at most 33 factors
Video solution:
Solution video thumbnail
Play video

Click to load, then click again to play

Written solution:
Since 2020=22⋅5⋅101,2020=2^2\cdot5\cdot101, it has (2+1)(1+1)(1+1)=12 (2+1)(1+1)(1+1)=12 positive factors.
Among those factors, only 11 and the primes 2,2, 5,5, and 101101 have fewer than three factors, while 44 has exactly three. The other 12−5=712-5=7 factors therefore have more than three factors.
Thus, the correct answer is B.
LIVE by Po-Shen Loh
Programs

LIVE Classes

Self-Paced Classes

Stars

Scholarship

About Us

Who Is Po-Shen Loh?

Email Contact

Newsletter

Jobs

Become a Star

For a more Thought Full world.

© 2026 Expii, Inc.