21433224 has 16 divisors (see below), whose sum is σ = 53583120. Its totient is φ = 7144400.

The previous prime is 21433219. The next prime is 21433231. The reversal of 21433224 is 42233412.

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 21433224.

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, 446502 + ... + 446549.

It is an arithmetic number, because the mean of its divisors is an integer number (3348945).

Almost surely, 2^21433224 is an apocalyptic number.

21433224 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21433224 is an abundant number, since it is smaller than the sum of its proper divisors (32149896).

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

21433224 is a wasteful number, since it uses less digits than its factorization.

21433224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 893060 (or 893056 counting only the distinct ones).

The product of its digits is 1152, while the sum is 21.

The square root of 21433224 is about 4629.6030067383. The cubic root of 21433224 is about 277.7767128611.

Adding to 21433224 its reverse (42233412), we get a palindrome (63666636).

The spelling of 21433224 in words is "twenty-one million, four hundred thirty-three thousand, two hundred twenty-four".