21103423412 has 12 divisors (see below), whose sum is σ = 36964664100. Its totient is φ = 10542090816.

The previous prime is 21103423403. The next prime is 21103423417. The reversal of 21103423412 is 21432430112.

It can be written as a sum of positive squares in 2 ways, for example, as 16097011876 + 5006411536 = 126874^2 + 70756^2 .

It is a super-2 number, since 2×21103423412² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21103423417) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2400287 + ... + 2409062.

It is an arithmetic number, because the mean of its divisors is an integer number (3080388675).

Almost surely, 2^21103423412 is an apocalyptic number.

It is an amenable number.

21103423412 is a deficient number, since it is larger than the sum of its proper divisors (15861240688).

21103423412 is a wasteful number, since it uses less digits than its factorization.

21103423412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4810450 (or 4810448 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 23.

Adding to 21103423412 its reverse (21432430112), we get a palindrome (42535853524).

The spelling of 21103423412 in words is "twenty-one billion, one hundred three million, four hundred twenty-three thousand, four hundred twelve".