21001203103 has 16 divisors (see below), whose sum is σ = 21499084800. Its totient is φ = 20509857760.

The previous prime is 21001203059. The next prime is 21001203109. The reversal of 21001203103 is 30130210012.

It is a cyclic number.

It is not a de Polignac number, because 21001203103 - 2⁹ = 21001202591 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 (21001203109) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3415650 + ... + 3421792.

It is an arithmetic number, because the mean of its divisors is an integer number (1343692800).

Almost surely, 2^21001203103 is an apocalyptic number.

21001203103 is a deficient number, since it is larger than the sum of its proper divisors (497881697).

21001203103 is a wasteful number, since it uses less digits than its factorization.

21001203103 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6662.

The product of its (nonzero) digits is 36, while the sum is 13.

Adding to 21001203103 its reverse (30130210012), we get a palindrome (51131413115).

The spelling of 21001203103 in words is "twenty-one billion, one million, two hundred three thousand, one hundred three".