21083524 has 72 divisors (see below), whose sum is σ = 47667200. Its totient is φ = 8149680.

The previous prime is 21083449. The next prime is 21083537. The reversal of 21083524 is 42538012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 165949 + ... + 166075.

Almost surely, 2^21083524 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 21083524, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23833600).

21083524 is an abundant number, since it is smaller than the sum of its proper divisors (26583676).

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

21083524 is a wasteful number, since it uses less digits than its factorization.

21083524 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174 (or 147 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 21083524 is about 4591.6798668897. The cubic root of 21083524 is about 276.2577058107.

The spelling of 21083524 in words is "twenty-one million, eighty-three thousand, five hundred twenty-four".