21103231003 has 4 divisors (see below), whose sum is σ = 21152194848. Its totient is φ = 21054267160.

The previous prime is 21103230989. The next prime is 21103231007. The reversal of 21103231003 is 30013230112.

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-21103231003 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21103231007) 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, 24481276 + ... + 24482137.

It is an arithmetic number, because the mean of its divisors is an integer number (5288048712).

Almost surely, 2^21103231003 is an apocalyptic number.

21103231003 is a deficient number, since it is larger than the sum of its proper divisors (48963845).

21103231003 is an equidigital number, since it uses as much as digits as its factorization.

21103231003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48963844.

The product of its (nonzero) digits is 108, while the sum is 16.

Adding to 21103231003 its reverse (30013230112), we get a palindrome (51116461115).

The spelling of 21103231003 in words is "twenty-one billion, one hundred three million, two hundred thirty-one thousand, three".