21311303 has 8 divisors (see below), whose sum is σ = 23179296. Its totient is φ = 19476000.

The previous prime is 21311261. The next prime is 21311347. The reversal of 21311303 is 30311312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21311303 - 2¹⁰ = 21310279 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 (21311393) 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 7 ways as a sum of consecutive naturals, for example, 6803 + ... + 9428.

It is an arithmetic number, because the mean of its divisors is an integer number (2897412).

Almost surely, 2^21311303 is an apocalyptic number.

21311303 is a deficient number, since it is larger than the sum of its proper divisors (1867993).

21311303 is a wasteful number, since it uses less digits than its factorization.

21311303 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16345.

The product of its (nonzero) digits is 54, while the sum is 14.

The square root of 21311303 is about 4616.4166839660. The cubic root of 21311303 is about 277.2490082338.

Adding to 21311303 its reverse (30311312), we get a palindrome (51622615).

Subtracting 21311303 from its reverse (30311312), we obtain a palindrome (9000009).

The spelling of 21311303 in words is "twenty-one million, three hundred eleven thousand, three hundred three".