I need to compute 987654321².

I'll break this down using the identity (a-b)² = a² - 2ab + b², where a = 1000000000 and b = 12345679.

So 987654321 = 1,000,000,000 - 12,345,679

Let me verify: 1,000,000,000 - 12,345,679 = 987,654,321 ✓

Now I'll compute directly using the standard multiplication algorithm instead.

987654321 × 987654321

Let me break this into parts:
987654321 × 987654321 = 987654321 × (900000000 + 87654321)

Actually, let me just carefully multiply this out:

987654321²

I'll use (987654321)² = (987654321)(987654321)

Breaking down:
- 987654321 × 1 = 987654321
- 987654321 × 20 = 19753086420
- 987654321 × 300 = 296296296300
- 987654321 × 4000 = 3950617284000
- 987654321 × 50000 = 49382716050000
- 987654321 × 600000 = 592592592600000
- 987654321 × 7000000 = 6913580247000000
- 987654321 × 80000000 = 79012345680000000
- 987654321 × 900000000 = 888888888900000000

Adding these up:
```
    888888888900000000
     79012345680000000
      6913580247000000
       592592592600000
        49382716050000
         3950617284000
          296296296300
           19753086420
              987654321
----------------------------
    975461057789971041
```

**987654321² = 975,461,057,789,971,041**
