Given integers $n, m$, calculate $\sum_{i=1} ^{m} n \mod i$.
### Input
- Contains 2 integers $1 \le n, m \le 10^{13}$.
### Output
- Print the answer modulo $10^9+7$.
### Constraints
- $1 \le n, m \le 10^{13}.$
### Example
Input:
```
3 4
```
Output:
```
4
```