21023003 has 2 divisors, whose sum is σ = 21023004. Its totient is φ = 21023002.

The previous prime is 21022997. The next prime is 21023017. The reversal of 21023003 is 30032012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21023003 - 2¹⁴ = 21006619 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21023083) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10511501 + 10511502.

It is an arithmetic number, because the mean of its divisors is an integer number (10511502).

Almost surely, 2^21023003 is an apocalyptic number.

21023003 is a deficient number, since it is larger than the sum of its proper divisors (1).

21023003 is an equidigital number, since it uses as much as digits as its factorization.

21023003 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36, while the sum is 11.

The square root of 21023003 is about 4585.0848410907. The cubic root of 21023003 is about 275.9931166455.

Adding to 21023003 its reverse (30032012), we get a palindrome (51055015).

Subtracting 21023003 from its reverse (30032012), we obtain a palindrome (9009009).

The spelling of 21023003 in words is "twenty-one million, twenty-three thousand, three".