144

is the only square in the Fibonacci sequence (apart from 1). Moreover, it is the 12th term of the Fibonacci sequence.

Reversing 12 and 144 in the equality 12² = 144 gives 441 = 21².

144 = (1 + 4)! + 4!

144⁵ = 27⁵ + 84⁵ + 110⁵ + 135⁵

= 71 + 73 (sum of consecutive primes)
= 3! x 4! = 4! + 5!
= 4² + 2 x 8²
= 6² + 3 x 6²

One of the largest numbers, that is not a power of 10, that has a specific name: 'gross' (= dozen dozen).

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