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PROJECT EULER · #0615

The Millionth Number with at Least One Million Prime Factors

Statement only · UnsolvedOriginal problem ↗

Consider the natural numbers having at least 5 prime factors, which don't have to be distinct.
Sorting these numbers by size gives a list which starts with:

  • 32=22222
  • 48=22223
  • 64=222222
  • 72=22233
  • 80=22225
  • 96=222223

So, for example, the fifth number with at least 5 prime factors is 80.

Find the millionth number with at least one million prime factors.
Give your answer modulo 123454321.

Write-up coming later

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