21502252 has 12 divisors (see below), whose sum is σ = 37855440. Its totient is φ = 10686416.

The previous prime is 21502241. The next prime is 21502267. The reversal of 21502252 is 25220512.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15427 + ... + 16762.

It is an arithmetic number, because the mean of its divisors is an integer number (3154620).

Almost surely, 2^21502252 is an apocalyptic number.

It is an amenable number.

21502252 is a deficient number, since it is larger than the sum of its proper divisors (16353188).

21502252 is a wasteful number, since it uses less digits than its factorization.

21502252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32360 (or 32358 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 19.

The square root of 21502252 is about 4637.0520807944. The cubic root of 21502252 is about 278.0745965472.

Adding to 21502252 its reverse (25220512), we get a palindrome (46722764).

The spelling of 21502252 in words is "twenty-one million, five hundred two thousand, two hundred fifty-two".