21819392 has 52 divisors (see below), whose sum is σ = 49932336. Its totient is φ = 9338880.

The previous prime is 21819383. The next prime is 21819403. The reversal of 21819392 is 29391812.

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, 28292 + ... + 29052.

Almost surely, 2^21819392 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 21819392, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24966168).

21819392 is an abundant number, since it is smaller than the sum of its proper divisors (28112944).

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

21819392 is an frugal number, since it uses more digits than its factorization.

21819392 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 792 (or 770 counting only the distinct ones).

The product of its digits is 7776, while the sum is 35.

The square root of 21819392 is about 4671.1232053972. The cubic root of 21819392 is about 279.4350513608.

The spelling of 21819392 in words is "twenty-one million, eight hundred nineteen thousand, three hundred ninety-two".