21211210303 has 4 divisors (see below), whose sum is σ = 21215084328. Its totient is φ = 21207336280.

The previous prime is 21211210297. The next prime is 21211210373. The reversal of 21211210303 is 30301211212.

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 21211210303 - 2⁵ = 21211210271 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 (21211210373) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1928788 + ... + 1939753.

It is an arithmetic number, because the mean of its divisors is an integer number (5303771082).

Almost surely, 2^21211210303 is an apocalyptic number.

21211210303 is a deficient number, since it is larger than the sum of its proper divisors (3874025).

21211210303 is an equidigital number, since it uses as much as digits as its factorization.

21211210303 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3874024.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21211210303 its reverse (30301211212), we get a palindrome (51512421515).

Subtracting 21211210303 from its reverse (30301211212), we obtain a palindrome (9090000909).

The spelling of 21211210303 in words is "twenty-one billion, two hundred eleven million, two hundred ten thousand, three hundred three".