144 is the natural number following 143 and preceding 145. 144 is a dozen dozens, or one gross. It is the twelfth Fibonacci number, and the largest one to also be a square. It is a Harshad number.
144 is a number that is divisible by the value of its φ function, which returns 48 in this case. Also, there are 21 solutions to the equation φ(x) = 144, more than any integer below 144, making it a highly totient number.
144 is the 12th square number, following 121 and preceding 169.
1445 = 275 + 845 + 1105 + 1335, the smallest number whose fifth power is a sum of less than five (smaller) fifth powers. This solution was found in 1967 by L.J. Lander and T.R. Parkin , and disproved a conjecture by Euler.
144 is also:
- The measurement, in cubits, of the wall of New Jerusalem shown by the seventh angel (Holy Bible, Revelation 21:17).
- The Intel 8086 instruction for no operation (NOP).
For the year AD 144, see 144.