81220320

Names of 81220320

• Cardinal: 81220320 can be written as Eighty-one million, two hundred twenty thousand, three hundred twenty.

Scientific notation

• Scientific notation: 8.122032 × 10⁷

Factors of 81220320

• Number of distinct prime factors ω(n): 4
• Total number of prime factors Ω(n): 12
• Sum of prime factors: 2099

Divisors of 81220320

• Number of divisors d(n): 144
• Complete list of divisors:
  1 2 3 4 5 6 8 9 10 12 15 16 18 20 24 27 30 32 36 40 45 48 54 60 72 80 81 90 96 108 120 135 144 160 162 180 216 240 243 270 288 324 360 405 432 480 486 540 648 720 810 864 972 1080 1215 1296 1440 1620 1944 2089 2160 2430 2592 3240 3888 4178 4320 4860 6267 6480 7776 8356 9720 10445 12534 12960 16712 18801 19440 20890 25068 31335 33424 37602 38880 41780 50136 56403 62670 66848 75204 83560 94005 100272 112806 125340 150408 167120 169209 188010 200544 225612 250680 282015 300816 334240 338418 376020 451224 501360 507627 564030 601632 676836 752040 846045 902448 1002720 1015254 1128060 1353672 1504080 1692090 1804896 2030508 2256120 2538135 2707344 3008160 3384180 4061016 4512240 5076270 5414688 6768360 8122032 9024480 10152540 13536720 16244064 20305080 27073440 40610160 81220320
• Sum of all divisors σ(n): 287567280
• Sum of proper divisors (its aliquot sum) s(n): 206346960
• 81220320 is an abundant number, because the sum of its proper divisors (206346960) is greater than itself. Its abundance is 125126640

Bases of 81220320

• Binary: 100110101110101001011100000₂
• Hexadecimal: 0x4D752E0
• Base-36: 1CCU00

Squares and roots of 81220320

• 81220320 squared (81220320²) is 6596740380902400
• 81220320 cubed (81220320³) is 535789364693814816768000
• The square root of 81220320 is 9012.2316881005
• The cube root of 81220320 is 433.0668078339

Scales and comparisons

• 81,220,320 seconds is equal to 2 years, 30 weeks, 2 days, 1 hour, 12 minutes.
• To count from 1 to 81,220,320 would take you about three years!

  This is a very rough estimate, based on a speaking rate of half a second every third order of magnitude. If you speak quickly, you could probably say any randomly-chosen number between one and a thousand in around half a second. Very big numbers obviously take longer to say, so we add half a second for every extra x1000. (We do not count involuntary pauses, bathroom breaks or the necessity of sleep in our calculation!)

• A cube with a volume of 81220320 cubic inches would be around 36.1 feet tall.

Recreational maths with 81220320

• 81220320 backwards is 02302218
• 81220320 is a Harshad number.
• The number of decimal digits it has is: 8
• The sum of 81220320's digits is 18
• More coming soon!