21044003 has 2 divisors, whose sum is σ = 21044004. Its totient is φ = 21044002.

The previous prime is 21043999. The next prime is 21044047. The reversal of 21044003 is 30044012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21044003 - 2² = 21043999 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21044063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10522001 + 10522002.

It is an arithmetic number, because the mean of its divisors is an integer number (10522002).

Almost surely, 2^21044003 is an apocalyptic number.

21044003 is a deficient number, since it is larger than the sum of its proper divisors (1).

21044003 is an equidigital number, since it uses as much as digits as its factorization.

21044003 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 21044003 is about 4587.3743034551. The cubic root of 21044003 is about 276.0849831069.

Adding to 21044003 its reverse (30044012), we get a palindrome (51088015).

Subtracting 21044003 from its reverse (30044012), we obtain a palindrome (9000009).

The spelling of 21044003 in words is "twenty-one million, forty-four thousand, three".