Problem 44384. Find the nearest prime number
Happy 5th birthday, Cody! Since 5 is a prime number, let's have some fun looking for other prime numbers.
Given a positive integer x, find the nearest prime number. Keep in mind that the nearest prime may be less than x.
Examples
nearestprime(5) = 5 nearestprime(36) = 37 nearestprime(200) = 199
NOTE: You may ignore cases in which two prime numbers are equally close to x. (e.g., x=12 --> 11 and 13 are both primes).
Solution Stats
Problem Comments
-
1 Comment
Tran Hiep Dinh
on 21 Mar 2019
Test case No. 5
x = 911;
y_correct = 911;
Should the nearest prime number for 911 have been 907?
Solution Comments
Show commentsGroup

Cody5:Easy
- 31 Problems
- 159 Finishers
- Energy of a photon
- Breaking Out of the Matrix
- The Top 5 Primes
- I Plead the Fifth
- Pentagonal Numbers
- Is this is a Tic Tac Toe X Win?
- Inscribed Pentagon?
- Circle/Pentagon Overlap
- Octoberfest festival
- Polarisation
- Missing five
- ASCII Birthday Cake
- Find the nearest prime number
- Extra safe primes
- 5 Prime Numbers
- Is this is a Tic Tac Toe X Win?
- Tick. Tock. Tick. Tock. Tick. Tock. Tick. Tock. Tick. Tock.
- MATLAB Counter
- Basic electricity in a dry situation
- How to subtract?
- Pernicious Anniversary Problem
- 5 Prime Numbers
- Is it really a 5?
- The glass half full
- Pi Digit Probability
- A Simple Tide Gauge with MATLAB
- Predicting life and death of a memory-less light bulb
- Write c^3 as sum of two squares a^2+b^2
- Van Eck's Sequence's nth member
- Sums of Multiple Pairs of Triangular Numbers
- Recaman Sequence - I
- Recaman Sequence - II
- Spot the First Occurrence of 5
- Energy of a photon
Problem Recent Solvers639
Problem Tags
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!