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id	challengeType	title
5900f5471000cf542c510059	5	Problem 474: Last digits of divisors

Description

For a positive integer n and digits d, we define F(n, d) as the number of the divisors of n whose last digits equal d. For example, F(84, 4) = 3. Among the divisors of 84 (1, 2, 3, 4, 6, 7, 12, 14, 21, 28, 42, 84), three of them (4, 14, 84) have the last digit 4.

We can also verify that F(12!, 12) = 11 and F(50!, 123) = 17888.

Find F(106!, 65432) modulo (1016 + 61).

Instructions

Tests

tests:
  - text: <code>euler474()</code> should return 9690646731515010.
    testString: assert.strictEqual(euler474(), 9690646731515010);

Challenge Seed

function euler474() {
  // Good luck!
  return true;
}

euler474();

Solution

// solution required

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