21386832 has 40 divisors (see below), whose sum is σ = 55752384. Its totient is φ = 7064064.

The previous prime is 21386821. The next prime is 21386857. The reversal of 21386832 is 23868312.

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 21386793 and 21386802.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3453 + ... + 7395.

Almost surely, 2^21386832 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 21386832, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27876192).

21386832 is an abundant number, since it is smaller than the sum of its proper divisors (34365552).

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

21386832 is a wasteful number, since it uses less digits than its factorization.

21386832 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4067 (or 4061 counting only the distinct ones).

The product of its digits is 13824, while the sum is 33.

The square root of 21386832 is about 4624.5899277666. The cubic root of 21386832 is about 277.5761531116.

The spelling of 21386832 in words is "twenty-one million, three hundred eighty-six thousand, eight hundred thirty-two".