Mark:
61) the 6th Euler number
62) the smallest number that can be written as the sum of of 3 distinct squares in 2 ways
63) the number of partially ordered sets of 5 elements
64) the smallest number with 7 divisors
65) the smallest number that becomes square if its reverse is either added to or subtracted from it
Which by remarkable coincidence is exactly what I have. What took you so long?
Whim:
61 = degrees farenheit reversed is the temperature in degrees celcius.

*
62 = house number of Wallace & Grommit.
63 = gallons in a hogshead.
64 = golden disks on the tower of Hanoi.
65 = retirement age. (Not according to Mark. If I was you I would shift to his plan)
* "With a little rounding." (Close enough)
Three lives have I.
Gentle enough to soothe the skin,
Light enough to caress the sky,
Hard enough to crack rocks.
I am
We are five little objects of an everyday sort
you will find us all in a tennis court
I am
I look flat, but I am deep,
Hidden realms I shelter.
Lives I take, but food I offer.
At times I am beautiful.
I can be calm, angry and turbulent.
I have no heart, but offer pleasure as well as death.
No man can own me, yet I encompass what all men must have.
I am
I heard of an invading, vanquishing army
sweeping across the land, liquid-quick;
conquering everything, quelling resistance.
With it came darkness, dimming the light.
Humans hid in their houses, while outside
spears pierced, shattering stone walls.
Uncountable soldiers smashed into the ground,
but each elicited life as he died;
when the army had vanished, advancing northward,
the land was green and growing, refreshed.
I am