21123010003 has 2 divisors, whose sum is σ = 21123010004. Its totient is φ = 21123010002.

The previous prime is 21123009991. The next prime is 21123010019. The reversal of 21123010003 is 30001032112.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21123010003 is a prime.

It is not a weakly prime, because it can be changed into another prime (21123010303) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10561505001 + 10561505002.

It is an arithmetic number, because the mean of its divisors is an integer number (10561505002).

Almost surely, 2^21123010003 is an apocalyptic number.

21123010003 is a deficient number, since it is larger than the sum of its proper divisors (1).

21123010003 is an equidigital number, since it uses as much as digits as its factorization.

21123010003 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36, while the sum is 13.

Adding to 21123010003 its reverse (30001032112), we get a palindrome (51124042115).

The spelling of 21123010003 in words is "twenty-one billion, one hundred twenty-three million, ten thousand, three".