The number 72450

Q: Is 72450 a prime number?

No. 72450 = 2 × 3^2 × 5^2 × 7 × 23, so it is divisible by 2.

72450 is a composite number with 72 divisors. Its prime factorisation is 2 × $3^{2}$ × $5^{2}$ × 7 × 23. Divisors (72): 1, 2, 3, 5, 6, 7, 9, 10, 14, 15, 18, 21, 23, 25, 30, 35 … 72450.

Number

Pick any whole number from 1 to 100,000.

72450 = 2 \times 3^{2} \times 5^{2} \times 7 \times 23

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How to work it out

1
What is special about 72450: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 18.
2
72450 is composite. Its prime factorisation is
$72450 = 2 \times 3^{2} \times 5^{2} \times 7 \times 23$
3
The divisors add up to 232128; without 72450 itself that is 159678, so 72450 is abundant (159678 is more than 72450). Euler's totient φ(72450) = 15840 numbers up to 72450 share no factor with it.
4
The digits of 72450 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 42 steps to reach 1.

LaTeX source of the formulas on this page

\[ 72450 = 2 \times 3^{2} \times 5^{2} \times 7 \times 23 \]

72450 at a glance

Property	Value
Type	composite
Number of divisors	72
Sum of divisors	232128
Euler totient φ(n)	15840
Square	5249002500
Cube	380290231125000
Square root	269.165377 (= 15√322)
Digit sum / digital root	18 / 9
Collatz steps to 1	42
Scientific notation	7.245 × $10^{4}$

72450 in other forms

Form	Value
In words	seventy-two thousand four hundred and fifty
Binary (base 2)	10001101100000010
Octal (base 8)	215402
Hexadecimal (base 16)	11B02
Base 3	10200101100
As time	72450 seconds = 20 h 7 min 30 s

Is 72450 divisible by 2 to 12?

Divisor	Answer	Rule
2	Yes (72450 ÷ 2 = 36225)	A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8).
3	Yes (72450 ÷ 3 = 24150)	A number is divisible by 3 if the digits add up to a multiple of 3.
4	No (remainder 2)	A number is divisible by 4 if the last two digits make a multiple of 4.
5	Yes (72450 ÷ 5 = 14490)	A number is divisible by 5 if the last digit is 0 or 5.
6	Yes (72450 ÷ 6 = 12075)	A number is divisible by 6 if it is divisible by both 2 and 3.
7	Yes (72450 ÷ 7 = 10350)	A number is divisible by 7 if double the last digit and subtract it from the rest: the result is a multiple of 7.
8	No (remainder 2)	A number is divisible by 8 if the last three digits make a multiple of 8.
9	Yes (72450 ÷ 9 = 8050)	A number is divisible by 9 if the digits add up to a multiple of 9.
10	Yes (72450 ÷ 10 = 7245)	A number is divisible by 10 if the last digit is 0.
11	No (remainder 4)	A number is divisible by 11 if the alternating sum of the digits is a multiple of 11.
12	No (remainder 6)	A number is divisible by 12 if it is divisible by both 3 and 4.

Questions

Is 72450 a prime number?

No. 72450 = 2 × $3^{2}$ × $5^{2}$ × 7 × 23, so it is divisible by 2.

What are the factors of 72450?

1, 2, 3, 5, 6, 7, 9, 10, 14, 15, 18, 21, 23, 25, 30, 35, 42, 45, 46, 50, 63, 69, 70, 75, 90, 105, 115, 126, 138, 150, 161, 175, 207, 210, 225, 230, 315, 322, 345, 350, 414, 450, 483, 525, 575, 630, 690, 805, 966, 1035, 1050, 1150, 1449, 1575, 1610, 1725, 2070, 2415, 2898, 3150, 3450, 4025, 4830, 5175, 7245, 8050, 10350, 12075, 14490, 24150, 36225, 72450.

What is 72450 in binary?

10001101100000010 (hexadecimal 11B02, octal 215402).

What is the square root of 72450?

About 269.1654, exactly 15√322.

Is 72450 divisible by 3?

Yes. Its digits add up to 18, a multiple of 3.

What is special about the number 72450?

72450 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 18.