21000001103 has 4 divisors (see below), whose sum is σ = 21207922008. Its totient is φ = 20792080200.

The previous prime is 21000001091. The next prime is 21000001153. The reversal of 21000001103 is 30110000012.

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 21000001103 - 2²⁴ = 20983223887 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 (21000001153) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 103960301 + ... + 103960502.

It is an arithmetic number, because the mean of its divisors is an integer number (5301980502).

Almost surely, 2^21000001103 is an apocalyptic number.

21000001103 is a deficient number, since it is larger than the sum of its proper divisors (207920905).

21000001103 is a wasteful number, since it uses less digits than its factorization.

21000001103 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207920904.

The product of its (nonzero) digits is 6, while the sum is 8.

Adding to 21000001103 its reverse (30110000012), we get a palindrome (51110001115).

The spelling of 21000001103 in words is "twenty-one billion, one thousand, one hundred three".