21323330 has 24 divisors (see below), whose sum is σ = 44649468. Its totient is φ = 7310688.

The previous prime is 21323311. The next prime is 21323371. The reversal of 21323330 is 3332312.

It can be written as a sum of positive squares in 2 ways, for example, as 17230801 + 4092529 = 4151^2 + 2023^2 .

It is a zygodrome in base 9.

It is a junction number, because it is equal to n+sod(n) for n = 21323299 and 21323308.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 21269 + ... + 22248.

Almost surely, 2^21323330 is an apocalyptic number.

21323330 is an abundant number, since it is smaller than the sum of its proper divisors (23326138).

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

21323330 is a wasteful number, since it uses less digits than its factorization.

21323330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43538 (or 43531 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 17.

The square root of 21323330 is about 4617.7191339448. The cubic root of 21323330 is about 277.3011534382.

Adding to 21323330 its reverse (3332312), we get a palindrome (24655642).

The spelling of 21323330 in words is "twenty-one million, three hundred twenty-three thousand, three hundred thirty".