21230203 has 2 divisors, whose sum is σ = 21230204. Its totient is φ = 21230202.

The previous prime is 21230179. The next prime is 21230213. The reversal of 21230203 is 30203212.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21230203 - 2⁵ = 21230171 is a prime.

It is not a weakly prime, because it can be changed into another prime (21230213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10615101 + 10615102.

It is an arithmetic number, because the mean of its divisors is an integer number (10615102).

Almost surely, 2^21230203 is an apocalyptic number.

21230203 is a deficient number, since it is larger than the sum of its proper divisors (1).

21230203 is an equidigital number, since it uses as much as digits as its factorization.

21230203 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 13.

The square root of 21230203 is about 4607.6244421611. The cubic root of 21230203 is about 276.8968715132.

Adding to 21230203 its reverse (30203212), we get a palindrome (51433415).

The spelling of 21230203 in words is "twenty-one million, two hundred thirty thousand, two hundred three".