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

def gcd(a, b):
    if a < b:
        a, b = b, a
    if a%b == 0:
        return b
    return gcd(b, a%b)

if P > 1:
    L = [0]*(N+1)
    n = 2
    num = P
    while n <= P**0.5:
        if P%n == 0:
            num = n
            break
        n += 1
    if num*2 <= N:
        ans = 0
        for i in range(2, N+1):
            if i*2 <= N:
                ans += 1
                continue
            n = 2
            while n <= i**0.5:
                if i%n == 0:
                    ans += 1
                    break
                n += 1
    else:
        ans = 1

print(ans)