Friday

August 1, 2014

August 1, 2014

Posted by **shaun** on Sunday, September 16, 2012 at 1:59pm.

- math -
**David Q/R**, Sunday, September 16, 2012 at 2:12pmAn obvious candidate is 5, so if you divide 555 by 5 you'll get 111. That's divisible by 3 (because the sum of the digits is divisible by 3, which is a useful quick check), so do that and you'll get 111/3 = 37. But 37 is a prime number, so you won't be able to find any more. So there should be just three, i.e. 3, 5 and 37.

**Related Questions**

MATH - Let’s agree to say that a positive integer is prime-like if it is not ...

math - Let’s agree to say that a positive integer is prime-like if it is not ...

Sigma over Phi - Let σ(n) be the sum of the positive divisors of an integer...

maths - Let σ(n) be the sum of the positive divisors of an integer n and &#...

mathematics - Let σ(n) be the sum of the positive divisors of an integer n ...

discrete math - which positive integers less than 12 are relatively prime to 13 ...

MATHS!!!! - For how many odd positive integers n<1000 does the number of ...

Maths - For how many odd positive integers n<1000 does the number of positive...

math - Let f:ℤ+ → ℤ+ be the function defined by: for each x &#...

math help please - Let f:ℤ+ → ℤ+ be the function defined by: ...