21433312 has 12 divisors (see below), whose sum is σ = 42196896. Its totient is φ = 10716640.

The previous prime is 21433289. The next prime is 21433319. The reversal of 21433312 is 21333412.

It is a self number, because there is not a number n which added to its sum of digits gives 21433312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21433319) 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 as a sum of consecutive naturals, namely, 334864 + ... + 334927.

It is an arithmetic number, because the mean of its divisors is an integer number (3516408).

Almost surely, 2^21433312 is an apocalyptic number.

It is an amenable number.

21433312 is a deficient number, since it is larger than the sum of its proper divisors (20763584).

21433312 is an equidigital number, since it uses as much as digits as its factorization.

21433312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 669801 (or 669793 counting only the distinct ones).

The product of its digits is 432, while the sum is 19.

The square root of 21433312 is about 4629.6125107832. The cubic root of 21433312 is about 277.7770930235. Note that the first 3 decimals are identical.

Adding to 21433312 its reverse (21333412), we get a palindrome (42766724).

The spelling of 21433312 in words is "twenty-one million, four hundred thirty-three thousand, three hundred twelve".