21243214203 has 4 divisors (see below), whose sum is σ = 28324285608. Its totient is φ = 14162142800.

The previous prime is 21243214199. The next prime is 21243214219. The reversal of 21243214203 is 30241234212.

It is a happy number.

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 21243214203 - 2² = 21243214199 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21243214243) 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, 3540535698 + ... + 3540535703.

It is an arithmetic number, because the mean of its divisors is an integer number (7081071402).

Almost surely, 2^21243214203 is an apocalyptic number.

21243214203 is a deficient number, since it is larger than the sum of its proper divisors (7081071405).

21243214203 is an equidigital number, since it uses as much as digits as its factorization.

21243214203 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7081071404.

The product of its (nonzero) digits is 2304, while the sum is 24.

Adding to 21243214203 its reverse (30241234212), we get a palindrome (51484448415).

The spelling of 21243214203 in words is "twenty-one billion, two hundred forty-three million, two hundred fourteen thousand, two hundred three".