21242652 has 12 divisors (see below), whose sum is σ = 49566216. Its totient is φ = 7080880.

The previous prime is 21242651. The next prime is 21242659. The reversal of 21242652 is 25624212.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21242651) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 885099 + ... + 885122.

It is an arithmetic number, because the mean of its divisors is an integer number (4130518).

Almost surely, 2^21242652 is an apocalyptic number.

It is an amenable number.

21242652 is an abundant number, since it is smaller than the sum of its proper divisors (28323564).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21242652 is a wasteful number, since it uses less digits than its factorization.

21242652 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1770228 (or 1770226 counting only the distinct ones).

The product of its digits is 1920, while the sum is 24.

The square root of 21242652 is about 4608.9751572340. The cubic root of 21242652 is about 276.9509833463.

Adding to 21242652 its reverse (25624212), we get a palindrome (46866864).

The spelling of 21242652 in words is "twenty-one million, two hundred forty-two thousand, six hundred fifty-two".