Mathematician Weiner said at the doctoral graduation ceremony: "The third power of my current age is a four-digit number, and the fourth power of my current age is a six-digit number, and these two numbers just contain the numbers 0 to 9 once each. So all numbers have to worship me, and I will do a great job in the field of mathematics." May I ask: How old was he when he graduated?
数学家维纳在博士毕业典礼上说："我现在年龄的三次方是一个四位数，现在年龄的四次方是一个六位数，并且这两个数刚好包含数字0至9各一次，所以所有数字都得朝拜我，我将在数学领域干出一番大事业．"请问：他是几岁毕业的？
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