21832 has 8 divisors (see below), whose sum is σ = 40950. Its totient is φ = 10912.

The previous prime is 21821. The next prime is 21839. The reversal of 21832 is 23812.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 12996 + 8836 = 114^2 + 94^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an alternating number because its digits alternate between even and odd.

It is not an unprimeable number, because it can be changed into a prime (21839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1357 + ... + 1372.

2²¹⁸³² is an apocalyptic number.

It is an amenable number.

21832 is a deficient number, since it is larger than the sum of its proper divisors (19118).

21832 is a wasteful number, since it uses less digits than its factorization.

21832 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2735 (or 2731 counting only the distinct ones).

The product of its digits is 96, while the sum is 16.

The square root of 21832 is about 147.7565565381. The cubic root of 21832 is about 27.9488863413.

Subtracting from 21832 its product of digits (96), we obtain a triangular number (21736 = T₂₀₈).

The spelling of 21832 in words is "twenty-one thousand, eight hundred thirty-two".