21303323 has 4 divisors (see below), whose sum is σ = 21334080. Its totient is φ = 21272568.

The previous prime is 21303319. The next prime is 21303341. The reversal of 21303323 is 32330312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21303323 - 2² = 21303319 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21303523) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14315 + ... + 15732.

It is an arithmetic number, because the mean of its divisors is an integer number (5333520).

Almost surely, 2^21303323 is an apocalyptic number.

21303323 is a deficient number, since it is larger than the sum of its proper divisors (30757).

21303323 is an equidigital number, since it uses as much as digits as its factorization.

21303323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30756.

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

The square root of 21303323 is about 4615.5522963130. The cubic root of 21303323 is about 277.2143986921.

Adding to 21303323 its reverse (32330312), we get a palindrome (53633635).

The spelling of 21303323 in words is "twenty-one million, three hundred three thousand, three hundred twenty-three".