21003000103 has 4 divisors (see below), whose sum is σ = 21005672328. Its totient is φ = 21000327880.

The previous prime is 21003000079. The next prime is 21003000131. The reversal of 21003000103 is 30100030012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21003000103 is a prime.

It is a super-2 number, since 2×21003000103² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21003000103.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21003000503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1324288 + ... + 1340053.

It is an arithmetic number, because the mean of its divisors is an integer number (5251418082).

Almost surely, 2^21003000103 is an apocalyptic number.

21003000103 is a deficient number, since it is larger than the sum of its proper divisors (2672225).

21003000103 is an equidigital number, since it uses as much as digits as its factorization.

21003000103 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2672224.

The product of its (nonzero) digits is 18, while the sum is 10.

Adding to 21003000103 its reverse (30100030012), we get a palindrome (51103030115).

The spelling of 21003000103 in words is "twenty-one billion, three million, one hundred three", and thus it is an aban number.