Your node is synching the entire blockchain and validating the consensus rules...

GRS

• NBXplorer headers height: 5454627
• The node is synchronized (Height: 5454627)

LTC

• NBXplorer headers height: 2839993
• The node is synchronized (Height: 2839993)
• NBXplorer is synchronizing... (Height: 2537721)

BTC

• NBXplorer headers height: 882359
• The node is synchronized (Height: 882359)

BTG

• NBXplorer headers height: 881062
• The node is synchronized (Height: 881062)

MONA

• NBXplorer headers height: 3572477
• The node is synchronized (Height: 3572477)

DASH

• NBXplorer headers height: 1874916
• Node headers height: 1874916
• Validated blocks: 1874916

Watch this video to understand the importance of blockchain synchronization.

If you really don't want to synch and you are familiar with the command line, check FastSync.