21324323 has 4 divisors (see below), whose sum is σ = 21778080. Its totient is φ = 20870568.

The previous prime is 21324313. The next prime is 21324361. The reversal of 21324323 is 32342312.

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 21324323 - 2¹⁴ = 21307939 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21324295 and 21324304.

It is not an unprimeable number, because it can be changed into a prime (21324313) 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, 226808 + ... + 226901.

It is an arithmetic number, because the mean of its divisors is an integer number (5444520).

Almost surely, 2^21324323 is an apocalyptic number.

21324323 is a deficient number, since it is larger than the sum of its proper divisors (453757).

21324323 is an equidigital number, since it uses as much as digits as its factorization.

21324323 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 453756.

The product of its digits is 864, while the sum is 20.

The square root of 21324323 is about 4617.8266533078. The cubic root of 21324323 is about 277.3054578905.

Adding to 21324323 its reverse (32342312), we get a palindrome (53666635).

The spelling of 21324323 in words is "twenty-one million, three hundred twenty-four thousand, three hundred twenty-three".