21323312 has 20 divisors (see below), whose sum is σ = 41399880. Its totient is φ = 10639488.

The previous prime is 21323311. The next prime is 21323371. The reversal of 21323312 is 21332312.

It is not an unprimeable number, because it can be changed into a prime (21323311) 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 3 ways as a sum of consecutive naturals, for example, 8828 + ... + 10980.

It is an arithmetic number, because the mean of its divisors is an integer number (2069994).

Almost surely, 2^21323312 is an apocalyptic number.

It is an amenable number.

21323312 is a deficient number, since it is larger than the sum of its proper divisors (20076568).

21323312 is a wasteful number, since it uses less digits than its factorization.

21323312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2780 (or 2774 counting only the distinct ones).

The product of its digits is 216, while the sum is 17.

The square root of 21323312 is about 4617.7171849302. The cubic root of 21323312 is about 277.3010754106.

Adding to 21323312 its reverse (21332312), we get a palindrome (42655624).

The spelling of 21323312 in words is "twenty-one million, three hundred twenty-three thousand, three hundred twelve".