21022203 has 4 divisors (see below), whose sum is σ = 28029608. Its totient is φ = 14014800.

The previous prime is 21022193. The next prime is 21022213. The reversal of 21022203 is 30222012.

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

It is an interprime number because it is at equal distance from previous prime (21022193) and next prime (21022213).

It is not a de Polignac number, because 21022203 - 2⁵ = 21022171 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21022213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3503698 + ... + 3503703.

It is an arithmetic number, because the mean of its divisors is an integer number (7007402).

Almost surely, 2^21022203 is an apocalyptic number.

21022203 is a deficient number, since it is larger than the sum of its proper divisors (7007405).

21022203 is an equidigital number, since it uses as much as digits as its factorization.

21022203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7007404.

The product of its (nonzero) digits is 48, while the sum is 12.

The square root of 21022203 is about 4584.9976008718. The cubic root of 21022203 is about 275.9896157614.

Adding to 21022203 its reverse (30222012), we get a palindrome (51244215).

The spelling of 21022203 in words is "twenty-one million, twenty-two thousand, two hundred three".