Try with
show crypto key mypubkey rsa
show crypto pki certificates
For which process are you using the key? EIGRP? VPN? other?
Rolando Valenzuela
ref: http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/security/a1/sec-a1-xe-3se-3850-cr-book/sec-a1-xe-3se-3850-cr-book_chapter_0110.html