How to format international phone numbers?

Today, the smartphone has received two strange calls from numbers +351214374386 and +18034898017077. Tried googling it, but searching or what not know about them. What is this strange number format? Somehow not very much it is similar to the international format.
April 19th 20 at 12:31
2 answers
April 19th 20 at 12:33
Oh, okay not able to... the second here will find, for example.
I hope the first will handle that.
Format is more than international
April 19th 20 at 12:35
Remove from the end of 7 digits and profit in Google

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