21532 has 12 divisors (see below), whose sum is σ = 43120. Its totient is φ = 9216.

The previous prime is 21529. The next prime is 21557. The reversal of 21532 is 23512.

21532 is an admirable number.

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, 357 + ... + 412.

2²¹⁵³² is an apocalyptic number.

It is an amenable number.

21532 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21560).

21532 is a wasteful number, since it uses less digits than its factorization.

21532 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 780 (or 778 counting only the distinct ones).

The product of its digits is 60, while the sum is 13.

The square root of 21532 is about 146.7378615082. The cubic root of 21532 is about 27.8202774613.

The spelling of 21532 in words is "twenty-one thousand, five hundred thirty-two".