# RSAPrivateCrtKey

Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)

# RSAPrivateCrtKey

```
interface RSAPrivateCrtKey : RSAPrivateKey
```

|----------------------------------------------------------------------------------------------------------------------------------------|
| [java.security.interfaces.RSAPrivateCrtKey](https://developer.android.com/reference/kotlin/java/security/interfaces/RSAPrivateCrtKey#) |

The interface to an RSA private key, as defined in the[PKCS#1 v2.2](https://tools.ietf.org/rfc/rfc8017.txt)standard, using the*Chinese Remainder Theorem*(CRT) information values.

## Summary

|                                                                                                                                                                  Constants                                                                                                                                                                  ||
|------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| static[Long](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-long/index.html) | [serialVersionUID](https://developer.android.com/reference/kotlin/java/security/interfaces/RSAPrivateCrtKey#serialVersionUID:kotlin.Long) The type fingerprint that is set to indicate serialization compatibility with a previous version of the type. |

|                                                                                                                            Public methods                                                                                                                            ||
|--------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| abstract[BigInteger](https://developer.android.com/reference/kotlin/java/math/BigInteger.html#)! | [getCrtCoefficient](https://developer.android.com/reference/kotlin/java/security/interfaces/RSAPrivateCrtKey#getCrtCoefficient())`()` Returns the crtCoefficient.  |
| abstract[BigInteger](https://developer.android.com/reference/kotlin/java/math/BigInteger.html#)! | [getPrimeExponentP](https://developer.android.com/reference/kotlin/java/security/interfaces/RSAPrivateCrtKey#getPrimeExponentP())`()` Returns the primeExponentP.  |
| abstract[BigInteger](https://developer.android.com/reference/kotlin/java/math/BigInteger.html#)! | [getPrimeExponentQ](https://developer.android.com/reference/kotlin/java/security/interfaces/RSAPrivateCrtKey#getPrimeExponentQ())`()` Returns the primeExponentQ.  |
| abstract[BigInteger](https://developer.android.com/reference/kotlin/java/math/BigInteger.html#)! | [getPrimeP](https://developer.android.com/reference/kotlin/java/security/interfaces/RSAPrivateCrtKey#getPrimeP())`()` Returns the primeP.                          |
| abstract[BigInteger](https://developer.android.com/reference/kotlin/java/math/BigInteger.html#)! | [getPrimeQ](https://developer.android.com/reference/kotlin/java/security/interfaces/RSAPrivateCrtKey#getPrimeQ())`()` Returns the primeQ.                          |
| abstract[BigInteger](https://developer.android.com/reference/kotlin/java/math/BigInteger.html#)! | [getPublicExponent](https://developer.android.com/reference/kotlin/java/security/interfaces/RSAPrivateCrtKey#getPublicExponent())`()` Returns the public exponent. |

| Inherited functions ||
|---|---|
| From class[RSAKey](https://developer.android.com/reference/kotlin/java/security/interfaces/RSAKey) |---------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | [BigInteger](https://developer.android.com/reference/kotlin/java/math/BigInteger.html#)!                                  | [getModulus](https://developer.android.com/reference/kotlin/java/security/interfaces/RSAKey#getModulus())`()` <br /> Returns the modulus. <br />                                                                                                                                                | | [AlgorithmParameterSpec](https://developer.android.com/reference/kotlin/java/security/spec/AlgorithmParameterSpec.html#)! | [getParams](https://developer.android.com/reference/kotlin/java/security/interfaces/RSAKey#getParams())`()` <br /> Returns the parameters associated with this key. The parameters are optional and may be either explicitly specified or implicitly created during key pair generation. <br /> | ||
| From class[RSAPrivateKey](https://developer.android.com/reference/kotlin/java/security/interfaces/RSAPrivateKey) |------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | [BigInteger](https://developer.android.com/reference/kotlin/java/math/BigInteger.html#)! | [getPrivateExponent](https://developer.android.com/reference/kotlin/java/security/interfaces/RSAPrivateKey#getPrivateExponent())`()` <br /> Returns the private exponent. <br /> | ||

## Constants

### serialVersionUID

Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)  
Deprecated in[API level 35](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)  

```
static val serialVersionUID: Long
```

**Deprecated:** *A`serialVersionUID`field in an interface is ineffectual. Do not use; no replacement.*

The type fingerprint that is set to indicate serialization compatibility with a previous version of the type.  

    Value: -5682214253527700368L

## Public methods

### getCrtCoefficient

Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)  

```
abstract fun getCrtCoefficient(): BigInteger!
```

Returns the crtCoefficient.

|                                                    Return                                                    ||
|------------------------------------------------------------------------------------------|--------------------|
| [BigInteger](https://developer.android.com/reference/kotlin/java/math/BigInteger.html#)! | the crtCoefficient |

### getPrimeExponentP

Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)  

```
abstract fun getPrimeExponentP(): BigInteger!
```

Returns the primeExponentP.

|                                                    Return                                                    ||
|------------------------------------------------------------------------------------------|--------------------|
| [BigInteger](https://developer.android.com/reference/kotlin/java/math/BigInteger.html#)! | the primeExponentP |

### getPrimeExponentQ

Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)  

```
abstract fun getPrimeExponentQ(): BigInteger!
```

Returns the primeExponentQ.

|                                                    Return                                                    ||
|------------------------------------------------------------------------------------------|--------------------|
| [BigInteger](https://developer.android.com/reference/kotlin/java/math/BigInteger.html#)! | the primeExponentQ |

### getPrimeP

Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)  

```
abstract fun getPrimeP(): BigInteger!
```

Returns the primeP.

|                                                Return                                                ||
|------------------------------------------------------------------------------------------|------------|
| [BigInteger](https://developer.android.com/reference/kotlin/java/math/BigInteger.html#)! | the primeP |

### getPrimeQ

Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)  

```
abstract fun getPrimeQ(): BigInteger!
```

Returns the primeQ.

|                                                Return                                                ||
|------------------------------------------------------------------------------------------|------------|
| [BigInteger](https://developer.android.com/reference/kotlin/java/math/BigInteger.html#)! | the primeQ |

### getPublicExponent

Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)  

```
abstract fun getPublicExponent(): BigInteger!
```

Returns the public exponent.

|                                                    Return                                                     ||
|------------------------------------------------------------------------------------------|---------------------|
| [BigInteger](https://developer.android.com/reference/kotlin/java/math/BigInteger.html#)! | the public exponent |