81357216349474479721

Names of 81357216349474479721

• Cardinal: 81357216349474479721 can be written as Eighty-one quintillion, three hundred fifty-seven quadrillion, two hundred sixteen trillion, three hundred forty-nine billion, four hundred seventy-four million, four hundred seventy-nine thousand, seven hundred twenty-one.

Scientific notation

• Scientific notation: 8.1357216349474479721 × 10¹⁹

Factors of 81357216349474479721

• Number of distinct prime factors ω(n): 3
• Total number of prime factors Ω(n): 5
• Sum of prime factors: 774651

Divisors of 81357216349474479721

• Number of divisors d(n): 18
• Complete list of divisors:
  1 241 751 180991 564001 773659 135924241 186451819 581017909 140025316069 436344449659 598548248281 105159012367819 144250127835721 449509734459031 108331846004626471 337581810578732281 81357216349474479721
• Sum of all divisors σ(n): 81803830100755428666
• Sum of proper divisors (its aliquot sum) s(n): 446613751280948945
• 81357216349474479721 is a deficient number, because the sum of its proper divisors (446613751280948945) is less than itself. Its deficiency is 80910602598193530776

Bases of 81357216349474479721

• Binary: 1000110100100001110111001010011100010001001000001110101111001101001₂
• Hexadecimal: 0x4690EE53889075E69
• Base-36: H643Q93AVL3ZD

Squares and roots of 81357216349474479721

• 81357216349474479721 squared (81357216349474479721²) is 6618996652135197588430445448263640237841
• 81357216349474479721 cubed (81357216349474479721³) is 538503142644210542684603852278865615804529905617004171322361
• The square root of 81357216349474479721 is 9019823520.9717091073
• The cube root of 81357216349474479721 is 4333099.8174202737

Scales and comparisons

• 81,357,216,349,474,479,721 seconds is equal to 293,274,701,009 years, 3 weeks, 3 days, 15 hours, 30 minutes, 7 seconds.
• To count from 1 to 81,357,216,349,474,479,721 would take you about two hundred ninety-three billion, two hundred seventy-four million, seven hundred one thousand and nine 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 81357216349474479721 cubic inches would be around 361091.7 feet tall.

Recreational maths with 81357216349474479721

• 81357216349474479721 backwards is 12797447494361275318
• The number of decimal digits it has is: 20
• The sum of 81357216349474479721's digits is 94
• More coming soon!