21538752 has 28 divisors (see below), whose sum is σ = 56988456. Its totient is φ = 7179520.

The previous prime is 21538747. The next prime is 21538757. The reversal of 21538752 is 25783512.

It is an interprime number because it is at equal distance from previous prime (21538747) and next prime (21538757).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21538757) 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, 55899 + ... + 56282.

It is an arithmetic number, because the mean of its divisors is an integer number (2035302).

Almost surely, 2^21538752 is an apocalyptic number.

It is an amenable number.

21538752 is an abundant number, since it is smaller than the sum of its proper divisors (35449704).

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

21538752 is a wasteful number, since it uses less digits than its factorization.

21538752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112196 (or 112186 counting only the distinct ones).

The product of its digits is 16800, while the sum is 33.

The square root of 21538752 is about 4640.9861021124. The cubic root of 21538752 is about 278.2318511632.

The spelling of 21538752 in words is "twenty-one million, five hundred thirty-eight thousand, seven hundred fifty-two".