21329392 has 40 divisors (see below), whose sum is σ = 47569376. Its totient is φ = 9075456.

The previous prime is 21329377. The next prime is 21329401. The reversal of 21329392 is 29392312.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16978 + ... + 18190.

Almost surely, 2^21329392 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 21329392, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23784688).

21329392 is an abundant number, since it is smaller than the sum of its proper divisors (26239984).

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

21329392 is a wasteful number, since it uses less digits than its factorization.

21329392 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1385 (or 1379 counting only the distinct ones).

The product of its digits is 5832, while the sum is 31.

The square root of 21329392 is about 4618.3754719598. The cubic root of 21329392 is about 277.3274288889.

The spelling of 21329392 in words is "twenty-one million, three hundred twenty-nine thousand, three hundred ninety-two".