Is the ncbi taxon code a number?

Question

[marongiu.luigi]

hello,

I would like to download sequences using ncbi's esearch -db "nucleotide" -query "txidX[Organism] where X is the code for a given organism. Are these code numbers (integers) or alphanumeric?

Thank you

Answer 1

[lieven.sterck]

NCBI taxonomy identifiers are all numbers (integers), but you can also query on scientific (or common) names