81000000

Names of 81000000

• Cardinal: 81000000 can be written as Eighty-one million.

Scientific notation

• Scientific notation: 8.1 × 10⁷

Factors of 81000000

• Number of distinct prime factors ω(n): 3
• Total number of prime factors Ω(n): 16
• Sum of prime factors: 10

Divisors of 81000000

• Number of divisors d(n): 245
• Complete list of divisors:
  1 2 3 4 5 6 8 9 10 12 15 16 18 20 24 25 27 30 32 36 40 45 48 50 54 60 64 72 75 80 81 90 96 100 108 120 125 135 144 150 160 162 180 192 200 216 225 240 250 270 288 300 320 324 360 375 400 405 432 450 480 500 540 576 600 625 648 675 720 750 800 810 864 900 960 1000 1080 1125 1200 1250 1296 1350 1440 1500 1600 1620 1728 1800 1875 2000 2025 2160 2250 2400 2500 2592 2700 2880 3000 3125 3240 3375 3600 3750 4000 4050 4320 4500 4800 5000 5184 5400 5625 6000 6250 6480 6750 7200 7500 8000 8100 8640 9000 9375 10000 10125 10800 11250 12000 12500 12960 13500 14400 15000 15625 16200 16875 18000 18750 20000 20250 21600 22500 24000 25000 25920 27000 28125 30000 31250 32400 33750 36000 37500 40000 40500 43200 45000 46875 50000 50625 54000 56250 60000 62500 64800 67500 72000 75000 81000 84375 90000 93750 100000 101250 108000 112500 120000 125000 129600 135000 140625 150000 162000 168750 180000 187500 200000 202500 216000 225000 250000 253125 270000 281250 300000 324000 337500 360000 375000 405000 421875 450000 500000 506250 540000 562500 600000 648000 675000 750000 810000 843750 900000 1000000 1012500 1080000 1125000 1265625 1350000 1500000 1620000 1687500 1800000 2025000 2250000 2531250 2700000 3000000 3240000 3375000 4050000 4500000 5062500 5400000 6750000 8100000 9000000 10125000 13500000 16200000 20250000 27000000 40500000 81000000
• Sum of all divisors σ(n): 300132877
• Sum of proper divisors (its aliquot sum) s(n): 219132877
• 81000000 is an abundant number, because the sum of its proper divisors (219132877) is greater than itself. Its abundance is 138132877

Bases of 81000000

• Binary: 100110100111111011001000000₂
• Hexadecimal: 0x4D3F640
• Base-36: 1C8400

Squares and roots of 81000000

• 81000000 squared (81000000²) is 6561000000000000
• 81000000 cubed (81000000³) is 531441000000000000000000
• 81000000 is a perfect square number. Its square root is 9000
• The cube root of 81000000 is 432.6748710923
• Being both a perfect square and a perfect cube, 81000000 is also a perfect sixth number.

Scales and comparisons

• 81,000,000 seconds is equal to 2 years, 29 weeks, 6 days, 12 hours.
• To count from 1 to 81,000,000 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 81000000 cubic inches would be around 36.1 feet tall.

Recreational maths with 81000000

• 81000000 backwards is 00000018
• 81000000 is a Harshad number.
• The number of decimal digits it has is: 8
• The sum of 81000000's digits is 9
• More coming soon!