21016528 has 40 divisors (see below), whose sum is σ = 44441600. Its totient is φ = 9569664.

The previous prime is 21016519. The next prime is 21016547. The reversal of 21016528 is 82561012.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 15793 + ... + 17071.

It is an arithmetic number, because the mean of its divisors is an integer number (1111040).

Almost surely, 2^21016528 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21016528, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22220800).

21016528 is an abundant number, since it is smaller than the sum of its proper divisors (23425072).

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

21016528 is a wasteful number, since it uses less digits than its factorization.

21016528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1379 (or 1373 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 21016528 is about 4584.3786929092. The cubic root of 21016528 is about 275.9647788143.

The spelling of 21016528 in words is "twenty-one million, sixteen thousand, five hundred twenty-eight".