'use strict'

const main = input => {
	const args = input.split('\n').map(arg => arg.split(' '))
	const x = args[0][0]

	if (x === '7') console.log('YES')
	else if (x === '5') console.log('YES')
	else if (x === '3') console.log('YES')
	else console.log('NO')
}

main(require('fs').readFileSync('/dev/stdin', 'utf8'))
