21000221203 has 4 divisors (see below), whose sum is σ = 22615622848. Its totient is φ = 19384819560.

The previous prime is 21000221189. The next prime is 21000221243. The reversal of 21000221203 is 30212200012.

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 21000221203 - 2⁵ = 21000221171 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13), and also a Moran number because the ratio is a prime number: 1615401631 = 21000221203 / (2 + 1 + 0 + 0 + 0 + 2 + 2 + 1 + 2 + 0 + 3).

It is not an unprimeable number, because it can be changed into a prime (21000221243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 807700803 + ... + 807700828.

It is an arithmetic number, because the mean of its divisors is an integer number (5653905712).

Almost surely, 2^21000221203 is an apocalyptic number.

21000221203 is a deficient number, since it is larger than the sum of its proper divisors (1615401645).

21000221203 is a wasteful number, since it uses less digits than its factorization.

21000221203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1615401644.

The product of its (nonzero) digits is 48, while the sum is 13.

Adding to 21000221203 its reverse (30212200012), we get a palindrome (51212421215).

The spelling of 21000221203 in words is "twenty-one billion, two hundred twenty-one thousand, two hundred three".