21303003 has 4 divisors (see below), whose sum is σ = 28404008. Its totient is φ = 14202000.

The previous prime is 21302993. The next prime is 21303011. The reversal of 21303003 is 30030312.

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 21303003 - 2²² = 17108699 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21303003.

It is not an unprimeable number, because it can be changed into a prime (21303203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3550498 + ... + 3550503.

It is an arithmetic number, because the mean of its divisors is an integer number (7101002).

Almost surely, 2^21303003 is an apocalyptic number.

21303003 is a deficient number, since it is larger than the sum of its proper divisors (7101005).

21303003 is an equidigital number, since it uses as much as digits as its factorization.

21303003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7101004.

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

The square root of 21303003 is about 4615.5176307756. The cubic root of 21303003 is about 277.2130106606.

Adding to 21303003 its reverse (30030312), we get a palindrome (51333315).

The spelling of 21303003 in words is "twenty-one million, three hundred three thousand, three".