21033203 has 2 divisors, whose sum is σ = 21033204. Its totient is φ = 21033202.

The previous prime is 21033193. The next prime is 21033223. The reversal of 21033203 is 30233012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21033203 - 2²⁴ = 4255987 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (21033223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10516601 + 10516602.

It is an arithmetic number, because the mean of its divisors is an integer number (10516602).

Almost surely, 2^21033203 is an apocalyptic number.

21033203 is a deficient number, since it is larger than the sum of its proper divisors (1).

21033203 is an equidigital number, since it uses as much as digits as its factorization.

21033203 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108, while the sum is 14.

The square root of 21033203 is about 4586.1970084156. The cubic root of 21033203 is about 276.0377451354.

Adding to 21033203 its reverse (30233012), we get a palindrome (51266215).

The spelling of 21033203 in words is "twenty-one million, thirty-three thousand, two hundred three".