The length of Earth's day is just under 24 hours, but it wasn't always that way. And even now, the day could be 2.5 times longer.
Here's What We Know
The Moon and the Sun did not allow the day on Earth to last 60 hours. It's all down to tidal forces. Lunar gravity slows the rotation of our planet. At the same time, the Sun affects the atmosphere and makes the Earth rotate faster.
Scientists at the University of Toronto believe that the Moon affects our planet an order of magnitude stronger than the Sun. Because of this, the Earth is still slowing down, not speeding up. But it wasn't always like this. More than 2 billion years ago, the Earth was in balance and the day lasted 4.5 hours less than it does now.
After the Sun and Moon balanced each other, things didn't change for 1.6 billion years. If not for this pause, our planet would be very different now without our usual biorhythms, as one revolution of the Earth around the axis would take 60 hours instead of the current 23 hours and 56 minutes.
Source: University of Toronto