70 (number) facts for kids

Seventy is the number that comes right after sixty-nine and just before seventy-one.

It's a special number because its prime factors are 2, 5, and 7. This means you can multiply these three prime numbers together to get 70 (2 × 5 × 7 = 70).

What Makes 70 Special?

Seventy is an interesting number in many ways. It is an even number, which means it can be divided by 2 without any remainder. It is also a composite number, because it has more than two factors (1, 2, 5, 7, 10, 14, 35, 70).

Math Facts About 70

• Seventy is the smallest number that is the sum of two prime numbers in six different ways.
• It is also a Harshad number (or Niven number). This means it can be divided by the sum of its digits (7 + 0 = 7, and 70 divided by 7 is 10).
• In Roman numerals, 70 is written as LXX.

Seventy in Everyday Life

The number 70 appears in many places around us.

Time and Calendars

• There are 70 years in seven decades.
• In some ancient calendars, there were periods related to 70 days or 70 weeks.

Science and Nature

• The atomic number for the element Ytterbium is 70. Ytterbium is a soft, silvery metal.
• Some animals have a lifespan that can be around 70 years, like certain types of parrots.

Sports and Games

• In basketball, a team scoring 70 points is a common score in a game.
• Many games or challenges might involve reaching a score of 70.

See also

• Number
• Prime number
• Composite number

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