21324003 has 4 divisors (see below), whose sum is σ = 28432008. Its totient is φ = 14216000.

The previous prime is 21323999. The next prime is 21324011. The reversal of 21324003 is 30042312.

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 21324003 - 2² = 21323999 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21324053) 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, 3553998 + ... + 3554003.

It is an arithmetic number, because the mean of its divisors is an integer number (7108002).

Almost surely, 2^21324003 is an apocalyptic number.

21324003 is a deficient number, since it is larger than the sum of its proper divisors (7108005).

21324003 is an equidigital number, since it uses as much as digits as its factorization.

21324003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7108004.

The product of its (nonzero) digits is 144, while the sum is 15.

The square root of 21324003 is about 4617.7920048439. The cubic root of 21324003 is about 277.3040707704.

Adding to 21324003 its reverse (30042312), we get a palindrome (51366315).

The spelling of 21324003 in words is "twenty-one million, three hundred twenty-four thousand, three".