# ATANH

**The ATANH function returns the hyperbolic arctangent of a number.**

This function takes a single [Number](../../variable-data-types/the-number-variable-data-type) as input. It outputs that Number's inverse hyperbolic tangent.

#### Declaration

```javascript
ATANH(number) -> hyperbolic_arctangent
```

####

#### Parameters

**number** (required, type: `Number`) The number to calculate the hyperbolic arctangent for.

#### Return Values

**hyperbolic\_arctangent** (type: `Number`) The hyperbolic arctangent of the given number.

#### Examples

The following example returns the hyperbolic arctangent of 0.5:

```javascript
ATANH(0.5) -> 0.5493061443340548
```
