21330003 has 4 divisors (see below), whose sum is σ = 28440008. Its totient is φ = 14220000.

The previous prime is 21329999. The next prime is 21330047. The reversal of 21330003 is 30003312.

It is a happy number.

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

It is not a de Polignac number, because 21330003 - 2² = 21329999 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21330073) 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, 3554998 + ... + 3555003.

It is an arithmetic number, because the mean of its divisors is an integer number (7110002).

Almost surely, 2^21330003 is an apocalyptic number.

21330003 is a deficient number, since it is larger than the sum of its proper divisors (7110005).

21330003 is an equidigital number, since it uses as much as digits as its factorization.

21330003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7110004.

The product of its (nonzero) digits is 54, while the sum is 12.

The square root of 21330003 is about 4618.4416202871. The cubic root of 21330003 is about 277.3300769632.

Adding to 21330003 its reverse (30003312), we get a palindrome (51333315).

The spelling of 21330003 in words is "twenty-one million, three hundred thirty thousand, three".