21052524 has 12 divisors (see below), whose sum is σ = 49122584. Its totient is φ = 7017504.

The previous prime is 21052489. The next prime is 21052547. The reversal of 21052524 is 42525012.

It is a happy number.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21052524.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 877177 + ... + 877200.

Almost surely, 2^21052524 is an apocalyptic number.

It is an amenable number.

21052524 is an abundant number, since it is smaller than the sum of its proper divisors (28070060).

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

21052524 is a wasteful number, since it uses less digits than its factorization.

21052524 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1754384 (or 1754382 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 21.

The square root of 21052524 is about 4588.3029542523. The cubic root of 21052524 is about 276.1222415869.

Adding to 21052524 its reverse (42525012), we get a palindrome (63577536).

The spelling of 21052524 in words is "twenty-one million, fifty-two thousand, five hundred twenty-four".