N,P = map(int,input().split())

import sys
if P == 1:
    print(1)
    exit()
prime = set()
dat = [0] * (N + 1)
for i in range(2,N + 1):
    if dat[i] == 0:
        prime.add(i)
        for j in range(i,N + 1,i):
            dat[j] = 1

if P in prime and P * 2 > N:
    print(1)
    exit()
dat = [0] * (N + 1)
inf = N // 2
for p in prime:
    if p <= inf:
        for j in range(p,N + 1,p):
            dat[j] = 1
print(sum(dat))