Returns the inverse hyperbolic tangent of the given number in radians.

**Sample Usage**

ATANH(0.2)

ATANH(C5)

**Syntax**

ATANH(number)

- number - The number for which the inverse hyperbolic tangent is to be computed.

**Examples**

ATANH(0.2) returns the inverse hyperbolic tangent of 0.2 in radians.

ATANH(C5) returns the inverse hyperbolic tangent of the number contained in C5.

**Notes**

- The number passed as an argument must be between -1 and 1, exclusive.