How to check if the number is prime number in Excel?

As we all known, a prime number is a natural number which contains only two distinct natural number divisors: One and itself. If you have a list of numbers in a worksheet, how could you check if the numbers are prime numbers?

Check if a number is prime number with array formula

Check if a number is prime number with User Defined Function


arrow blue right bubble Check if a number is prime number with array formula

The following formula can help you identify the number whether it is a prime number or not, please do as this:

1. Enter the following formula into a blank cell – C2 for example beside your data:

=IF(A2=2,"Prime",IF(AND(MOD(A2,ROW(INDIRECT("2:"&ROUNDUP(SQRT(A2),0))))<>0),"Prime","Not Prime")) (A2 is the cell contains the number that you want to check), and then press Ctrl + Shift + Enter keys together, and you will get the result, if the number is prime, it will display “Prime” in the cell, if not, “Not Prime” will be displayed, see screenshot:

doc check if prime 1

2. Then select the cell C2, and drag the fill handle down to the cells which you want to apply this formula, and all the numbers will be identified if is prime number or not. See screenshot:

doc check if prime 2


arrow blue right bubble Check if a number is prime number with User Defined Function

The following User Defined Function also can help you to check the numbers if prime or not, please do as follows:

1. Hold down the ALT + F11 keys to open the Microsoft Visual Basic for Applications window.

2. Click Insert > Module, and paste the following code in the Module Window.

VBA code: Check if a number is prime or not:

Function CheckPrime(Numb As Single) As Boolean
'Updateby Extendoffice
    Dim X As Long
    If Numb < 2 Or (Numb <> 2 And Numb Mod 2 = 0) _
     Or Numb <> Int(Numb) Then Exit Function
    For X = 3 To Sqr(Numb) Step 2
        If Numb Mod X = 0 Then Exit Function
    Next
    CheckPrime = True
End Function

3. Then save and close this code, go back to the worksheet, and enter this formula: =checkprime(A2) into a blank cell beside your number list, and then drag the fill handle down to the cells which you want to contain this formula, if the number is prime number, it will display TRUE, if not, it will display FALSE, see screenshot:

doc check if prime 3


The Best Office Productivity Tools

Kutools for Excel Solves Most of Your Problems, and Increases Your Productivity by 80%

  • Reuse: Quickly insert complex formulas, charts and anything that you have used before; Encrypt Cells with password; Create Mailing List and send emails...
  • Super Formula Bar (easily edit multiple lines of text and formula); Reading Layout (easily read and edit large numbers of cells); Paste to Filtered Range...
  • Merge Cells/Rows/Columns without losing Data; Split Cells Content; Combine Duplicate Rows/Columns... Prevent Duplicate Cells; Compare Ranges...
  • Select Duplicate or Unique Rows; Select Blank Rows (all cells are empty); Super Find and Fuzzy Find in Many Workbooks; Random Select...
  • Exact Copy Multiple Cells without changing formula reference; Auto Create References to Multiple Sheets; Insert Bullets, Check Boxes and more...
  • Extract Text, Add Text, Remove by Position, Remove Space; Create and Print Paging Subtotals; Convert Between Cells Content and Comments...
  • Super Filter (save and apply filter schemes to other sheets); Advanced Sort by month/week/day, frequency and more; Special Filter by bold, italic...
  • Combine Workbooks and WorkSheets; Merge Tables based on key columns; Split Data into Multiple Sheets; Batch Convert xls, xlsx and PDF...
  • More than 300 powerful features. Supports Office/Excel 2007-2019 and 365. Supports all languages. Easy deploying in your enterprise or organization. Full features 30-day free trial. 60-day money back guarantee.
kte tab 201905

Office Tab Brings Tabbed interface to Office, and Make Your Work Much Easier

  • Enable tabbed editing and reading in Word, Excel, PowerPoint, Publisher, Access, Visio and Project.
  • Open and create multiple documents in new tabs of the same window, rather than in new windows.
  • Increases your productivity by 50%, and reduces hundreds of mouse clicks for you every day!
officetab bottom
Say something here...
symbols left.
You are guest ( Sign Up? )
or post as a guest, but your post won't be published automatically.
Loading comment... The comment will be refreshed after 00:00.