The number fifteen | number (2024)

FAQs

What two numbers make 15? ›

In this case, the pair factors of 15 are: 3 × 5 = 15, hence, (3,5) is a pair factor. 1 × 15 = 15 is also a pair factor. The positive pair factors of 15 are (1,15) and (3,5).

It's obvious that 9+6, 6+9, 8+7 and 7+8 have sums of 15.

Answer: 16 is the number just after 15.

15 in words is written as “Fifteen”. In Mathematics, 15 is a natural number used in many arithmetic operations as a value.

There are four factors of 15, i.e, 1, 3, 5 and 15. Hence, the smallest factor is 1 and the greatest factor of 15 is 15, itself. The sum of all factors of 15 is equal to 24. Pair factors of 15 are the integers that give the original number 15 when multiplied together in pairs.

As the product of two sacred numbers (3 × 5), 15 naturally has religious significance. In ancient Nineveh the goddess Ishtar was served by 15 priests, and the city had 15 gates.

Factors of 15 by Prime Factorization

For example, the factors of 15 are 1, 3, 5, and 15 because each of those numbers divides evenly into 15 with no remainder.

How do you represent 15? ›

To represent 15, we use a cluster of five tally marks, then add another cluster of five tally marks and then add another of five tally marks.

In decimal, 15 contains the digits 1 and 5 and is the result of adding together the integers from 1 to 5 (1 + 2 + 3 + 4 + 5 = 15). The only other number with this property (in decimal) is 27.

15, 30, 45, 60, 75, 90, 105, 120, 135, 150, 165, 180, 195, 210, 225, 240, 255, 270, 285, 300, 315, 330, 345, 360, 375, 390, 405, 420, 435, 450, 465, 480, 495, 510, 525, 540, 555, 570, 585, 600, 615, 630, 645, 660, 675, 690, 705, 720, 735, … All numbers can be divided or the product of 15 is a multiple of 15.

Hence, the required natural numbers are 5 and 10.