21012132103 has 16 divisors (see below), whose sum is σ = 22763943936. Its totient is φ = 19337677920.

The previous prime is 21012132083. The next prime is 21012132137. The reversal of 21012132103 is 30123121012.

It is a cyclic number.

It is not a de Polignac number, because 21012132103 - 2²¹ = 21010034951 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 (21012132173) 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 15 ways as a sum of consecutive naturals, for example, 38176 + ... + 208522.

It is an arithmetic number, because the mean of its divisors is an integer number (1422746496).

Almost surely, 2^21012132103 is an apocalyptic number.

21012132103 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21012132103 is a deficient number, since it is larger than the sum of its proper divisors (1751811833).

21012132103 is a wasteful number, since it uses less digits than its factorization.

21012132103 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170574.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21012132103 its reverse (30123121012), we get a palindrome (51135253115).

The spelling of 21012132103 in words is "twenty-one billion, twelve million, one hundred thirty-two thousand, one hundred three".