Describe the bug

We have multiple BigNumber libraries in use right now, bignumber.js, bn.js, etc

You can see this from app/util/number/index.js

import { BN, stripHexPrefix } from 'ethereumjs-util';
import { utils as ethersUtils } from 'ethers';
import convert from 'ethjs-unit';
import {
  BNToHex,
  hexToBN as controllerHexToBN,
} from '@metamask/controller-utils';
import numberToBN from 'number-to-bn';
import BigNumber from 'bignumber.js';

Would be good to settle on a single library.

Expected behavior

A singular BigNumber library should be used to prevent incompatibilities or strange/unexpected behavior from happening.

Screenshots/Recordings

No response

Steps to reproduce

n/a

Error messages or log output

No response

Version

7.24.0

Build type

None

Device

Android, iOS

Operating system

iOS, Android

Additional context

No response

Severity

No response