21130103 has 4 divisors (see below), whose sum is σ = 21141600. Its totient is φ = 21118608.

The previous prime is 21130079. The next prime is 21130111. The reversal of 21130103 is 30103112.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21130103 - 2¹⁶ = 21064567 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 (21132103) 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, 2303 + ... + 6896.

It is an arithmetic number, because the mean of its divisors is an integer number (5285400).

Almost surely, 2^21130103 is an apocalyptic number.

21130103 is a deficient number, since it is larger than the sum of its proper divisors (11497).

21130103 is an equidigital number, since it uses as much as digits as its factorization.

21130103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11496.

The product of its (nonzero) digits is 18, while the sum is 11.

The square root of 21130103 is about 4596.7491774079. The cubic root of 21130103 is about 276.4609979356.

Adding to 21130103 its reverse (30103112), we get a palindrome (51233215).

The spelling of 21130103 in words is "twenty-one million, one hundred thirty thousand, one hundred three".