A prime number is one that has only two factors: one and itself.You can tell if a number is prime quickly by using the Laws of Divisibility:Numbers that end in 0, 2, 4, 6, and 8 are divisible by 2.If the sum of a number's digit is divisible by 3, the number itself is divisible by 3.If the last two digits of a number are divisible by 4, the number itself is divisible by 4.If a number ends in 0 or 5, it is divisible by 5.If a number is divisible by both 2 and 3, it is divisible by 6.If you double the last digit and subtract it from the rest of the number and the answer is 0 or divisible by 7, it is divisible by 7. For example, 4364: 4 doubled is 8. 436 - 8 = 424. You still cannot readily tell if the number is divisible by 7, so you can do it again: 4 doubled is 8. 42 - 8 = 34. 34 is not divisible by 7 so 436 is not divisible by 7If the last three digits of a number are divisible by 8, the number itself is divisible by 8.If the sum of the digits of a number is divisible by 9, the number itself is divisible by 9.If a number ends with 0, it is divisible by 10.If you add every other digit and then subtract the rest of the digits and the answer is 0 or is divisible by 11, the number itself is divisible by 11. For example: 1364: 1+ 6 = 7 and 7 - 3 - 4 = 0. The number is divisible by 11.If the number is divisible by 3 and 4, it is divisible by 12.There are more divisibility rules that can be used for large numbers.
420
420
a number is divisible by 12 if the number is also divisible by both 3 and 7. You mean a number is divisible by 21 if it is divisible by 3 and 7.
The smallest number divisible by 2 3 4 5 6 7 9 10 and 11 is 13,860.
I am a 3 digit number divisible by 7 but not 2 the sum of my digits is 4 what number am I
280
To find the least 4-digit number divisible by 2, 3, 4, 5, 6, and 7, we need to find the least common multiple (LCM) of these numbers. The LCM of 2, 3, 4, 5, 6, and 7 is 420. The smallest 4-digit number divisible by 420 is 1050. Therefore, 1050 is the least 4-digit number divisible by 2, 3, 4, 5, 6, and 7.
301, if you mean that it's divisible by 7 and its DIGITS add up to 4
2463. The trick is that a number is divisible by 3 if and only if the sum of its digits is divisible by 3. 1+3+2+4 = 10 (not divisible by 3), while 2+4+6+3 = 15 (divisible by 3).
A prime number is one that has only two factors: one and itself.You can tell if a number is prime quickly by using the Laws of Divisibility:Numbers that end in 0, 2, 4, 6, and 8 are divisible by 2.If the sum of a number's digit is divisible by 3, the number itself is divisible by 3.If the last two digits of a number are divisible by 4, the number itself is divisible by 4.If a number ends in 0 or 5, it is divisible by 5.If a number is divisible by both 2 and 3, it is divisible by 6.If you double the last digit and subtract it from the rest of the number and the answer is 0 or divisible by 7, it is divisible by 7. For example, 4364: 4 doubled is 8. 436 - 8 = 424. You still cannot readily tell if the number is divisible by 7, so you can do it again: 4 doubled is 8. 42 - 8 = 34. 34 is not divisible by 7 so 436 is not divisible by 7If the last three digits of a number are divisible by 8, the number itself is divisible by 8.If the sum of the digits of a number is divisible by 9, the number itself is divisible by 9.If a number ends with 0, it is divisible by 10.If you add every other digit and then subtract the rest of the digits and the answer is 0 or is divisible by 11, the number itself is divisible by 11. For example: 1364: 1+ 6 = 7 and 7 - 3 - 4 = 0. The number is divisible by 11.If the number is divisible by 3 and 4, it is divisible by 12.There are more divisibility rules that can be used for large numbers.
-4
The divisibility rule for 3 is as follows: If the sum of the digits of a number is divisible by 3 then the number is divisible by 3. For example, the number 21 is divisible by 3 since 2+1=3, and 3 is divisible by 3. The number 49 is not divisible by 3 since 4+9=13, and 13 is not divisible by 3.
1- Any number is divisible by 1. 2- Any even number is divisible by 2. 3- If its digits add up to a number divisible by 3, the whole number is divisible by 3. 4- If the last two digits are divisible by 4, the whole number is divisible by 4. 5- If it ends in 5 or 0, the whole number is divisible by 5. 6- If it's even and also divisible by 3, the whole number is divisible by 6. 7- There is no rule for 7. 8- If the last three digits are divisible by 8, the whole number is divisible by 8. 9- If its digits add up to a number divisible by 9, the whole number is divisible by 9. 10- If it ends in 0, the whole number is divisible by 10.
30
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420