21100012003 has 4 divisors (see below), whose sum is σ = 24114299440. Its totient is φ = 18085724568.

The previous prime is 21100012001. The next prime is 21100012007. The reversal of 21100012003 is 30021000112.

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

It is a cyclic number.

It is not a de Polignac number, because 21100012003 - 2¹ = 21100012001 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21100012001) 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, 1507143708 + ... + 1507143721.

It is an arithmetic number, because the mean of its divisors is an integer number (6028574860).

Almost surely, 2^21100012003 is an apocalyptic number.

21100012003 is a deficient number, since it is larger than the sum of its proper divisors (3014287437).

21100012003 is an equidigital number, since it uses as much as digits as its factorization.

21100012003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3014287436.

The product of its (nonzero) digits is 12, while the sum is 10.

Adding to 21100012003 its reverse (30021000112), we get a palindrome (51121012115).

The spelling of 21100012003 in words is "twenty-one billion, one hundred million, twelve thousand, three".