My angular program, I need to pass the number which is more than 20 digit to the API request.

num: any;

this.num = 2019111122001424290521878689;
console.log(this.num); // It displays "2.0191111220014244e+27"

I tried to change string from number as below

console.log(this.num.toString()); // It displays "2.0191111220014244e+27"

My expectation is that I need to pass the original big integer into the API request. If I pass as below, it goes as "2.0191111220014244e+27".

BTW, I tried BigInt(this.num), which gives difference number.

Suggest me

My angular program, I need to pass the number which is more than 20 digit to the API request.

num: any;

this.num = 2019111122001424290521878689;
console.log(this.num); // It displays "2.0191111220014244e+27"

I tried to change string from number as below

console.log(this.num.toString()); // It displays "2.0191111220014244e+27"

My expectation is that I need to pass the original big integer into the API request. If I pass as below, it goes as "2.0191111220014244e+27".

BTW, I tried BigInt(this.num), which gives difference number.

Suggest me

• javascript
• typescript
• biginteger

• 1 can't you keep this data as a string, do you need to do any calculation with it ? – Nicolas Commented Nov 11, 2019 at 14:41
• Actually, I got this data from some external API where I got only integer. But, I can convert into a string and can pass it string in our API request. – Muthukumar Marichamy Commented Nov 11, 2019 at 14:44
• In your case, i think that would make more sens, let your API handle big numbers. – Nicolas Commented Nov 11, 2019 at 14:45
• No, My API does support only string. So, I must to convert into string. I am not sure about mathjs npm.. Anyidea other than mathjs? – Muthukumar Marichamy Commented Nov 11, 2019 at 14:46

4 Answers 4

In JavaScript, big integer literals have the letter n as a suffix:

var bigNum = 2019111122001424290521878689n;
console.log(bigNum);

For more information, see

• MDN JavaScript Reference - BigInt

If you got a large number (> SAFE_INTEGER) from an API, in JSON format, and you want to get the exact value, as as string, you unfortunately can't use JSON.parse(), as it will use the number type and lose precision.

There are alternative JSON parsers out there like LosslessJSON that might solve your problem.

You can use BigInt. BigInt is a built-in object that provides a way to represent whole numbers larger than 253 - 1, which is the largest number JavaScript can reliably represent with the Number primitive. BigInt can be used for arbitrarily large integers.

const theBiggestInt = 9007199254740991n;

const alsoHuge = BigInt(9007199254740991);
// ↪ 9007199254740991n

const hugeString = BigInt("9007199254740991");
// ↪ 9007199254740991n

const hugeHex = BigInt("0x1fffffffffffff");
// ↪ 9007199254740991n

const hugeBin = BigInt("0b11111111111111111111111111111111111111111111111111111");
// ↪ 9007199254740991n

BigInt is similar to Number in some ways, but also differs in a few key matters — it cannot be used with methods in the built-in Math object and cannot be mixed with instances of Number in operations; they must be coerced to the same type. Be careful coercing values back and forth, however, as the precision of a BigInt may be lost when it is coerced to a Number.

Refer to https://developer.mozilla/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt

The problem is that the number you have there is not an integer. Javascript can only store integers up to the value given by Number.MAX_SAFE_INTEGER. In chrome, this number is 9007199254740991.

The number you have is actually a floating point number, and converting it between floating point and integer will loose some precision.