33.1. A six-digit number starts with one. If this one is moved to the end of the number, the resulting number will be three times the given number. Find the given number.

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\text { (7-10 grades) }
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33.1. The desired six-digit number has the form $1 \overline{a b c d e}$. According to the problem, $3 \cdot 1 \overline{a b c d e}=\overline{a b c d e} 1$ or $3(100000+\overline{a b c d e})=1+10 \cdot \overline{a b c d e}$. From this, $7 \cdot \overline{a b c d e}=299999$, i.e., $\overline{a b c d e}=42857$. Therefore, the desired number is 142857.