21 times 24 is 504. In symbols: 21 × 24 = 504, and 24 × 21 = 504 too.
21 × 24 means adding 21 to itself 24 times: that is 24 copies of 21, which add up to 504.
21, 42, 63, 84, 105, 126, 147, 168, 189, 210, 231, 252, ... (keep going to the 24th multiple). The 24th multiple of 21 is 504.
21 × 24 = 21 × 20 + 21 × 4 = 420 + 84 = 504.
Halve one number and double the other: 21 × 24 = 12 × 42 = 504.
504 ÷ 21 = 24
504 ÷ 24 = 21
504 is even. Prime factorization: 2 × 2 × 2 × 3 × 3 × 7.
| Multiplication | Answer |
|---|---|
| 20 × 24 | 480 |
| 22 × 24 | 528 |
| 21 × 23 | 483 |
| 21 × 25 | 525 |
| 21 × 26 | 546 |
| 21 × 22 | 462 |
| 23 × 24 | 552 |
| 19 × 24 | 456 |
Other numbers? Browse the multiplication table, the squares and cubes or the exponent calculator.