21303123103 has 4 divisors (see below), whose sum is σ = 21305660688. Its totient is φ = 21300585520.

The previous prime is 21303123067. The next prime is 21303123143. The reversal of 21303123103 is 30132130312.

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-21303123103 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21303123143) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1256158 + ... + 1273003.

It is an arithmetic number, because the mean of its divisors is an integer number (5326415172).

Almost surely, 2^21303123103 is an apocalyptic number.

21303123103 is a deficient number, since it is larger than the sum of its proper divisors (2537585).

21303123103 is an equidigital number, since it uses as much as digits as its factorization.

21303123103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2537584.

The product of its (nonzero) digits is 324, while the sum is 19.

Adding to 21303123103 its reverse (30132130312), we get a palindrome (51435253415).

The spelling of 21303123103 in words is "twenty-one billion, three hundred three million, one hundred twenty-three thousand, one hundred three".