The next number in the series is 65.
You'll notice that each succeeding number gets a progressive multiple of 3 added to the previous number in the series. The first number is 2, and the next number 5 is 2+(3x1). The next number 11 is 5+(3x2), and so forth. To obtain the number following 47, we simply add to 47 the 6th multiple of 3 (because 47 is the sixth number in the series), that is, 47+(3x6) = 65.
65. 2+1*3=5 5+2*3=11 11+3*3=20 20+4*3=32 32+5*3=47 47+6*3=65
59 is the next number in this series.
The next number in the series is 67.
A single number such as 61205041320 does not make a series.
A single number, such as 12848384 does not make a series.
One number does not make a sequence (nor a series).
There is no series of number: just one very large number!
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8
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25