21213110203 has 4 divisors (see below), whose sum is σ = 21468689928. Its totient is φ = 20957530480.

The previous prime is 21213110167. The next prime is 21213110227. The reversal of 21213110203 is 30201131212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21213110203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21213113203) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 127789738 + ... + 127789903.

It is an arithmetic number, because the mean of its divisors is an integer number (5367172482).

Almost surely, 2^21213110203 is an apocalyptic number.

21213110203 is a deficient number, since it is larger than the sum of its proper divisors (255579725).

21213110203 is an equidigital number, since it uses as much as digits as its factorization.

21213110203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255579724.

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

Adding to 21213110203 its reverse (30201131212), we get a palindrome (51414241415).

The spelling of 21213110203 in words is "twenty-one billion, two hundred thirteen million, one hundred ten thousand, two hundred three".