The differences are not the same so the sequence is not arithmetic.
The sequence starts with a zero, so it cannot be geometric, or an exponential (power) sequence.
The quartic: (2n4 - 19n3 + 64n2 - 83n + 36)/6 fits the 5 points. That gives the next term as 55.
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A single number, such as 21357, does not define a sequence.
It is not possible to identify a sequence when given only one number, as in this questions.
If you mean: 9, 19, 39, 69 then the next number in the sequence is 109
5
121498