21135303 has 16 divisors (see below), whose sum is σ = 35784960. Its totient is φ = 12077208.

The previous prime is 21135293. The next prime is 21135311. The reversal of 21135303 is 30353112.

It is not a de Polignac number, because 21135303 - 2⁸ = 21135047 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21135503) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55725 + ... + 56102.

It is an arithmetic number, because the mean of its divisors is an integer number (2236560).

Almost surely, 2^21135303 is an apocalyptic number.

21135303 is a deficient number, since it is larger than the sum of its proper divisors (14649657).

21135303 is a wasteful number, since it uses less digits than its factorization.

21135303 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111843 (or 111837 counting only the distinct ones).

The product of its (nonzero) digits is 270, while the sum is 18.

The square root of 21135303 is about 4597.3147597266. The cubic root of 21135303 is about 276.4836745765.

Adding to 21135303 its reverse (30353112), we get a palindrome (51488415).

The spelling of 21135303 in words is "twenty-one million, one hundred thirty-five thousand, three hundred three".