140 (number)

140 (one hundred [and] forty) is the natural number following 139 and preceding 141.

140 is an abundant number and a harmonic divisor number.

[1] It is the sum of the squares of the first seven integers, which makes it a square pyramidal number.

140 is an odious number because it has an odd number of ones in its binary representation.

The sum of Euler's totient function φ(x) over the first twenty-one integers is 140.