21050303 has 2 divisors, whose sum is σ = 21050304. Its totient is φ = 21050302.

The previous prime is 21050297. The next prime is 21050311. The reversal of 21050303 is 30305012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21050303 - 2⁴ = 21050287 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21050363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10525151 + 10525152.

It is an arithmetic number, because the mean of its divisors is an integer number (10525152).

Almost surely, 2^21050303 is an apocalyptic number.

21050303 is a deficient number, since it is larger than the sum of its proper divisors (1).

21050303 is an equidigital number, since it uses as much as digits as its factorization.

21050303 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 90, while the sum is 14.

The square root of 21050303 is about 4588.0609193863. The cubic root of 21050303 is about 276.1125311270.

Adding to 21050303 its reverse (30305012), we get a palindrome (51355315).

The spelling of 21050303 in words is "twenty-one million, fifty thousand, three hundred three".