We need to identify the number that does not follow the pattern in the given series:
\[
396, 462, 572, 427, 671, 264.
\]
Step 1: Compute the sum of the digits for each number
\[
396: 3 + 9 + 6 = 18
\]
\[
462: 4 + 6 + 2 = 12
\]
\[
572: 5 + 7 + 2 = 14
\]
\[
427: 4 + 2 + 7 = 13
\]
\[
671: 6 + 7 + 1 = 14
\]
\[
264: 2 + 6 + 4 = 12
\]
Step 2: Identify the odd one out
Observing the sums of the digits:
- \( 18, 12, 14, 14, 12 \) are all even numbers.
- \( 13 \) (from 427) is the only odd number.
Since all numbers except \( 427 \) have even sums, the number that does not follow the pattern is:
\[
\boxed{427}
\]