Express the number as a product of its factors.

The factors of 70: 

70 = 1 × 70.

70 = 2 × 35.

70 = 5 × 14.

70 = 7 × 10.

Factors of 70 are 1, 2, 5,7, 10,14,35 and 70. Since the number has more than two factors,

it is composite.

The number 70 is a composite number.