21524252 has 12 divisors (see below), whose sum is σ = 38543736. Its totient is φ = 10511760.

The previous prime is 21524249. The next prime is 21524263. The reversal of 21524252 is 25242512.

It is a hoax number, since the sum of its digits (23) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

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, 62399 + ... + 62742.

It is an arithmetic number, because the mean of its divisors is an integer number (3211978).

Almost surely, 2^21524252 is an apocalyptic number.

It is an amenable number.

21524252 is a deficient number, since it is larger than the sum of its proper divisors (17019484).

21524252 is a wasteful number, since it uses less digits than its factorization.

21524252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125188 (or 125186 counting only the distinct ones).

The product of its digits is 1600, while the sum is 23.

The square root of 21524252 is about 4639.4236711040. The cubic root of 21524252 is about 278.1694014370.

Adding to 21524252 its reverse (25242512), we get a palindrome (46766764).

The spelling of 21524252 in words is "twenty-one million, five hundred twenty-four thousand, two hundred fifty-two".