Sum of Divisors

CSESMathematicsOpen on judge ↗

Let \sigma(n) denote the sum of divisors of an integer n. For example, \sigma(12)=1+2+3+4+6+12=28. Your task is to calculate the sum \sum_{i=1}^n \sigma(i) modulo 10^9+7. Input The only input line has an integer n. Output Print \sum_{i=1}^n \sigma(i) modulo 10^9+7. Constraints - 1 \le n \le 10^{12} Example Input: 5 Output: 21

HINT LADDERno hints yet

L1 Observation

L2 Technique

L3 Approach

L4 Pseudo-code

🔒

L5 Full solution

L5 unlocks only if you insist twice

solution.cppC++17

CodeSearch Tutor

Hints, not spoilers — it won’t hand over the full solution unless you insist.

voice by Sarvam AI