21103412111 has 16 divisors (see below), whose sum is σ = 23756255424. Its totient is φ = 18639988224.

The previous prime is 21103412063. The next prime is 21103412131. The reversal of 21103412111 is 11121430112.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21103412111 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21103412111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21103412131) 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 15 ways as a sum of consecutive naturals, for example, 488456 + ... + 529901.

It is an arithmetic number, because the mean of its divisors is an integer number (1484765964).

Almost surely, 2^21103412111 is an apocalyptic number.

21103412111 is a deficient number, since it is larger than the sum of its proper divisors (2652843313).

21103412111 is a wasteful number, since it uses less digits than its factorization.

21103412111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1018450.

The product of its (nonzero) digits is 48, while the sum is 17.

Adding to 21103412111 its reverse (11121430112), we get a palindrome (32224842223).

The spelling of 21103412111 in words is "twenty-one billion, one hundred three million, four hundred twelve thousand, one hundred eleven".