# coding: UTF-8
import sys
#sys.setrecursionlimit(n)
import heapq
import re
import bisect
import random
import math
import itertools
from collections import defaultdict, deque
from copy import deepcopy
from decimal import *

def find(x):
    if node[x] < 0:
        return x
    else:
        node[x] = find(node[x])
        return node[x]

def unite(x, y):
    x = find(x)
    y = find(y)

    if x != y:
        if rank[x] > rank[y]:
            node[x] += node[y]
            node[y] = x
        else:
            node[y] += node[x]
            node[x] = y
            if rank[x] == rank[y]:
                rank[y] += 1

def is_same(x, y):
    return find(x) == find(y)

def size(x):
    return -node[find(x)]

n, p = map(int, input().split())
node = [-1 for i in range(n + 1)]
rank = [0 for _ in range(n + 1)]
used = [False for _ in range(n+1)]
for i in range(2,int(n // 2) + 1):
    if used[i]:
        continue
    for j in range(i, n + 1, i):
        if i + j > n:
            break
        used[i + j] = True
        unite(i, i + j)
print(size(find(p)))