Python 2, 51 bytes

f=lambda n,k=2:n/k/k*[f]and[(k,n/k)][n%k:]+f(n,k+1)

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Python 2, 52 bytes

lambda n:[(n/k,k)for k in range(1,n)if n%k<1<=n/k/k]

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Python 2, 51 bytes

f=lambda n,k=2:n/k/k*[f]and[(k,n/k)][n%k:]+f(n,k+1)

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51 bytes (thanks to Luis Mendo for a byte)

lambda n:[(n/k,k)for k in range(1,n)if(k*k<=n)>n%k]

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51 bytes

lambda n:[(n/k,k)for k in range(1,n)if n/k/k>n%k*n]

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Python 2, 51 bytes

f=lambda n,k=2:n/k/k*[f]and[(k,n/k)][n%k:]+f(n,k+1)

Try it online!

Python 2, 51 bytes

f=lambda n,k=2:n/k/k*[f]and[(k,n/k)][n%k:]+f(n,k+1)

Try it online!

Python 2, 52 bytes

lambda n:[(n/k,k)for k in range(1,n)if n%k<1<=n/k/k]

Try it online!