Regarding your first question.The pipe works as follows:
numberValue | number: {minIntegerDigits}.{minFractionDigits}-{maxFractionDigits}
minFractionDigits: Minimum number of integer digits to show after the decimal point
maxFractionDigits: Maximum number of integer digits to show after the decimal point
2.Regarding your second question, Filter to zero decimal places as follows:
{{ numberValue | number: '1.0-0' }}
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