As described in the linked Wikipedia page:
"Integers between 2**n and 2**(n+1) round to a multiple of 2**(n-23)"
Since your value is between 2**24 and 2**25, the result will thus be rounded to multiples of 2.
a = 16799999
print(2**24 < a)
> True
print(a < 2**25)
> True

print(torch.tensor(a).float()) # 16799999
> tensor(16800000.) # rounded up

print(torch.tensor(a-1).float()) # 16799998
> tensor(16799998.) # representable

print(torch.tensor(a+2).float()) # 16800001 
> tensor(16800000.) # rounded down

print(torch.tensor(a+3).float()) # 16800002
> tensor(16800002.) # representable