21223296 has 160 divisors (see below), whose sum is σ = 66646800. Its totient is φ = 6690816.

The previous prime is 21223291. The next prime is 21223297. The reversal of 21223296 is 69232212.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits and also a Zuckerman number because it is divisible by the product of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21223291) by changing a digit.

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 19 ways as a sum of consecutive naturals, for example, 238420 + ... + 238508.

Almost surely, 2^21223296 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 21223296, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33323400).

21223296 is an abundant number, since it is smaller than the sum of its proper divisors (45423504).

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

21223296 is an equidigital number, since it uses as much as digits as its factorization.

21223296 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138 (or 117 counting only the distinct ones).

The product of its digits is 2592, while the sum is 27.

The square root of 21223296 is about 4606.8748626374. The cubic root of 21223296 is about 276.8668398623.

The spelling of 21223296 in words is "twenty-one million, two hundred twenty-three thousand, two hundred ninety-six".