21439296 has 112 divisors (see below), whose sum is σ = 66446400. Its totient is φ = 6759936.

The previous prime is 21439291. The next prime is 21439307. The reversal of 21439296 is 69293412.

It is a Harshad number since it is a multiple of its sum of digits (36).

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

It is a self number, because there is not a number n which added to its sum of digits gives 21439296.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21439291) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32506 + ... + 33158.

Almost surely, 2^21439296 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 21439296, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33223200).

21439296 is an abundant number, since it is smaller than the sum of its proper divisors (45007104).

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

21439296 is a wasteful number, since it uses less digits than its factorization.

21439296 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 693 (or 677 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 21439296 is about 4630.2587400706. The cubic root of 21439296 is about 277.8029416255.

The spelling of 21439296 in words is "twenty-one million, four hundred thirty-nine thousand, two hundred ninety-six".