21021122203 has 4 divisors (see below), whose sum is σ = 21030998040. Its totient is φ = 21011246368.

The previous prime is 21021122197. The next prime is 21021122233. The reversal of 21021122203 is 30222112012.

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 21021122203 - 2¹³ = 21021114011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21021122233) 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, 4934725 + ... + 4938982.

It is an arithmetic number, because the mean of its divisors is an integer number (5257749510).

Almost surely, 2^21021122203 is an apocalyptic number.

21021122203 is a deficient number, since it is larger than the sum of its proper divisors (9875837).

21021122203 is an equidigital number, since it uses as much as digits as its factorization.

21021122203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9875836.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 21021122203 its reverse (30222112012), we get a palindrome (51243234215).

The spelling of 21021122203 in words is "twenty-one billion, twenty-one million, one hundred twenty-two thousand, two hundred three".