21202003 has 2 divisors, whose sum is σ = 21202004. Its totient is φ = 21202002.

The previous prime is 21202001. The next prime is 21202033. The reversal of 21202003 is 30020212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21202003 - 2¹ = 21202001 is a prime.

Together with 21202001, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21202001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601001 + 10601002.

It is an arithmetic number, because the mean of its divisors is an integer number (10601002).

Almost surely, 2^21202003 is an apocalyptic number.

21202003 is a deficient number, since it is larger than the sum of its proper divisors (1).

21202003 is an equidigital number, since it uses as much as digits as its factorization.

21202003 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24, while the sum is 10.

The square root of 21202003 is about 4604.5632800516. The cubic root of 21202003 is about 276.7742168270.

Adding to 21202003 its reverse (30020212), we get a palindrome (51222215).

The spelling of 21202003 in words is "twenty-one million, two hundred two thousand, three".