It's a style guide thing in my op, but if you're writing out numerals that large in a block paragraph, I would recommend using the commas for readability purposes - a string of text numerals is hard to parse - and it also sounds better (I'm relatively sure most people insert pauses between logical digit groupings).

I'll admit to influence being ex APS (Australian Public Service), but we do tend to do a lot of writing and our style guidelines have been hammered out specifically with a view to making sure that the relevant information gets to the eyes of the target reader, in a form with the lowest chance of it being mangled.

Paraphrasing our guide (specific reference below) and personal experience, three other suggestions:

• If you can, place the numeric form after the string. The numbers are much easier to scan for in text, and give a quicker indication of 'sizeness'.

  five million, two hundred and fifty thousand, four hundred and twenty-two (5 250 422)

• I'd also suggest retaining the and within digit blocks. In my op, it's more natural but also binds the numerals together indicating who belongs to which group.

four hundred and twenty-two

not

four hundred twenty two

• Finally, hyphenate between the tens and ones of a group of digits, again for readability.

two million and fifty-four thousand, nine hundred and ninety-nine.

not

two million and fifty four thousand, nine hundred and ninety nine.

I thought it was a bit silly when first having to internalise the style guide, but after a while it starts to make sense, for example in a straight side-by-side:

Five million six hundred twenty nine thousand two hundred ninety six

Five million, six hundred and twenty-nine thousand, two hundred and ninety-six (5 629 296)

Of course, your internal guides (or the prevailing style in your area, I have a funny feeling AmE might drop the internal ands for instance) will have their own suggestions, and consistency is king with something like this.

Source: Old habits from a stint in the Australian Public Service as a policy officer, and the Style Manual (6th ed), pg 176. (ISBN 978-0-7016-3648-7)

It's a style guide thing in my op, but if you're writing out numerals that large in a block paragraph, I would recommend using the commas for readability purposes - a string of text numerals is hard to parse - and it also sounds better (I'm relatively sure most people insert pauses between logical digit groupings).

I'll admit to influence being ex APS (Australian Public Service), but we do tend to do a lot of writing and our style guidelines have been hammered out specifically with a view to making sure that the relevant information gets to the eyes of the target reader, in a form with the lowest chance of it being mangled.

Paraphrasing our guide (specific reference below) and personal experience, three other suggestions:

• If you can, place the numeric form after the string. The numbers are much easier to scan for in text, and give a quicker indication of 'sizeness'.

  five million, two hundred and fifty thousand, four hundred and twenty-two (5 250 422)

• I'd also suggest retaining the and within digit blocks. In my op, it's more natural but also binds the numerals together indicating who belongs to which group.

four hundred and twenty-two

not

four hundred twenty two

• Finally, hyphenate between the tens and ones of a group of digits, again for readability.

two million, fifty-four thousand, nine hundred and ninety-nine.

not

two million, fifty four thousand, nine hundred and ninety nine.

I thought it was a bit silly when first having to internalise the style guide, but after a while it starts to make sense, for example in a straight side-by-side:

Five million six hundred twenty nine thousand two hundred ninety six

Five million, six hundred and twenty-nine thousand, two hundred and ninety-six (5 629 296)

Of course, your internal guides (or the prevailing style in your area, I have a funny feeling AmE might drop the internal ands for instance) will have their own suggestions, and consistency is king with something like this.

Source: Old habits from a stint in the Australian Public Service as a policy officer, and the Style Manual (6th ed), pg 176. (ISBN 978-0-7016-3648-7)

It's a style guide thing in my op, but if you're writing out numerals that large in a block paragraph, I would recommend using the commas for readability purposes - a string of text numerals is hard to parse - and it also sounds better (I'm relatively sure most people insert pauses between logical digit groupings).

I'll admit to influence being ex APS (Australian Public Service), but we do tend to do a lot of writing and our style guidelines have been hammered out specifically with a view to making sure that the relevant information gets to the eyes of the relevant person, in a way that ensures the lowest chance of it being mangled.

Paraphrasing our guide (specific reference below) and personal experience, three other suggestions:

• If you can, place the numeric form after the string. The numbers are much easier to scan for in text, and give a quicker indication of 'sizeness'.

  five million, two hundred and fifty thousand, four hundred and twenty-two (5 250 422)

• I'd also suggest retaining the and within digit blocks. In my op, it's more natural but also binds the numerals together indicating who belongs to which group.

four hundred and twenty-two

not

four hundred twenty two

• Finally, hyphenate between the tens and ones of a group of digits, again for readability.

two million and fifty-four thousand, nine hundred and ninety-nine.

not

two million and fifty four thousand, nine hundred and ninety nine.

I thought it was a bit silly when first having to internalise the style guide, but after a while it starts to make sense, for example in a straight side-by-side:

Five million six hundred twenty nine thousand two hundred ninety six

Five million, six hundred and twenty-nine thousand, two hundred and ninety-six (5 629 296)

Of course, your internal guides will have their own suggestions, and consistency is king with something like this.

Source: Old habits from a stint in the Australian Public Service as a policy officer, and the Style Manual (6th ed), pg 176. (ISBN 978-0-7016-3648-7)

It's a style guide thing in my op, but if you're writing out numerals that large in a block paragraph, I would recommend using the commas for readability purposes - a string of text numerals is hard to parse - and it also sounds better (I'm relatively sure most people insert pauses between logical digit groupings).

I'll admit to influence being ex APS (Australian Public Service), but we do tend to do a lot of writing and our style guidelines have been hammered out specifically with a view to making sure that the relevant information gets to the eyes of the target reader, in a form with the lowest chance of it being mangled.

Paraphrasing our guide (specific reference below) and personal experience, three other suggestions:

• If you can, place the numeric form after the string. The numbers are much easier to scan for in text, and give a quicker indication of 'sizeness'.

  five million, two hundred and fifty thousand, four hundred and twenty-two (5 250 422)

• I'd also suggest retaining the and within digit blocks. In my op, it's more natural but also binds the numerals together indicating who belongs to which group.

four hundred and twenty-two

not

four hundred twenty two

• Finally, hyphenate between the tens and ones of a group of digits, again for readability.

two million and fifty-four thousand, nine hundred and ninety-nine.

not

two million and fifty four thousand, nine hundred and ninety nine.

I thought it was a bit silly when first having to internalise the style guide, but after a while it starts to make sense, for example in a straight side-by-side:

Five million six hundred twenty nine thousand two hundred ninety six

Five million, six hundred and twenty-nine thousand, two hundred and ninety-six (5 629 296)

Of course, your internal guides (or the prevailing style in your area, I have a funny feeling AmE might drop the internal ands for instance) will have their own suggestions, and consistency is king with something like this.

Source: Old habits from a stint in the Australian Public Service as a policy officer, and the Style Manual (6th ed), pg 176. (ISBN 978-0-7016-3648-7)