21130303 has 4 divisors (see below), whose sum is σ = 22373280. Its totient is φ = 19887328.

The previous prime is 21130301. The next prime is 21130321. The reversal of 21130303 is 30303112.

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 21130303 - 2¹ = 21130301 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21130301) 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, 621463 + ... + 621496.

It is an arithmetic number, because the mean of its divisors is an integer number (5593320).

Almost surely, 2^21130303 is an apocalyptic number.

21130303 is a deficient number, since it is larger than the sum of its proper divisors (1242977).

21130303 is a wasteful number, since it uses less digits than its factorization.

21130303 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1242976.

The product of its (nonzero) digits is 54, while the sum is 13.

The square root of 21130303 is about 4596.7709318608. The cubic root of 21130303 is about 276.4618701828.

Adding to 21130303 its reverse (30303112), we get a palindrome (51433415).

The spelling of 21130303 in words is "twenty-one million, one hundred thirty thousand, three hundred three".