21427392 has 112 divisors (see below), whose sum is σ = 65836800. Its totient is φ = 6024192.

The previous prime is 21427381. The next prime is 21427447. The reversal of 21427392 is 29372412.

It is a tau number, because it is divible by the number of its divisors (112).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 143734 + ... + 143882.

Almost surely, 2^21427392 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 21427392, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32918400).

21427392 is an abundant number, since it is smaller than the sum of its proper divisors (44409408).

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

21427392 is a wasteful number, since it uses less digits than its factorization.

21427392 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278 (or 268 counting only the distinct ones).

The product of its digits is 6048, while the sum is 30.

The square root of 21427392 is about 4628.9731042641. The cubic root of 21427392 is about 277.7515161424.

The spelling of 21427392 in words is "twenty-one million, four hundred twenty-seven thousand, three hundred ninety-two".