import os
import sys
from io import BytesIO, IOBase

BUFSIZE = 8192


class FastIO(IOBase):
	newlines = 0
	
	def __init__(self, file):
		self._fd = file.fileno()
		self.buffer = BytesIO()
		self.writable = "x" in file.mode or "r" not in file.mode
		self.write = self.buffer.write if self.writable else None
	
	def read(self):
		while True:
			b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
			if not b:
				break
			ptr = self.buffer.tell()
			self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
		self.newlines = 0
		return self.buffer.read()
	
	def readline(self):
		while self.newlines == 0:
			b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
			self.newlines = b.count(b"\n")+(not b)
			ptr = self.buffer.tell()
			self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
		self.newlines -= 1
		return self.buffer.readline()
	
	def flush(self):
		if self.writable:
			os.write(self._fd, self.buffer.getvalue())
			self.buffer.truncate(0), self.buffer.seek(0)


class IOWrapper(IOBase):
	def __init__(self, file):
		self.buffer = FastIO(file)
		self.flush = self.buffer.flush
		self.writable = self.buffer.writable
		self.write = lambda s:self.buffer.write(s.encode("ascii"))
		self.read = lambda:self.buffer.read().decode("ascii")
		self.readline = lambda:self.buffer.readline().decode("ascii")


sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
input = lambda:sys.stdin.readline().rstrip("\r\n")

# バーンサイドの補題
# t ごとまわす
# let g[i] = gcd(t, A[i])
# prod_i A[i] / g[i]
# t | lcm(A)
# ok!

def makediv(n):
	lower_divisors , upper_divisors = [], []
	i = 1
	while i*i <= n:
		if n % i == 0:
			lower_divisors.append(i)
			if i != n // i:
				upper_divisors.append(n//i)
		i += 1
	return lower_divisors + upper_divisors[::-1]


from math import gcd
mod = 998244353
n, m = map(int,input().split())
a = list(map(int,input().split()))
lcm = 1

for i in range(n):
	lcm = lcm * a[i] // gcd(a[i], lcm)

g = makediv(lcm)
f = len(g)
dp = [0] * f
ans = 0

for i in range(f-1,-1,-1):
	r = 0
	for j in range(n):
		r += gcd(g[i], a[j])
	tmp = pow(m, r, mod)
	dp[i] = lcm // g[i]
	for j in range(i+1, f):
		if g[j] % g[i] == 0:
			dp[i] -= dp[j]
	dp[i] %= mod
	ans += dp[i] * tmp
	ans %= mod

ans *= pow(lcm, mod-2, mod)
ans %= mod
print(ans)