21120012100111 has 4 divisors (see below), whose sum is σ = 22038273495792. Its totient is φ = 20201750704432.

The previous prime is 21120012100093. The next prime is 21120012100163. The reversal of 21120012100111 is 11100121002112.

It is a happy number.

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 21120012100111 - 2¹¹ = 21120012098063 is a prime.

It is a super-2 number, since 2×21120012100111² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21120012100091 and 21120012100100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120012100181) 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, 459130697806 + ... + 459130697851.

It is an arithmetic number, because the mean of its divisors is an integer number (5509568373948).

Almost surely, 2^{21120012100111} is an apocalyptic number.

21120012100111 is a deficient number, since it is larger than the sum of its proper divisors (918261395681).

21120012100111 is an equidigital number, since it uses as much as digits as its factorization.

21120012100111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 918261395680.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21120012100111 its reverse (11100121002112), we get a palindrome (32220133102223).

The spelling of 21120012100111 in words is "twenty-one trillion, one hundred twenty billion, twelve million, one hundred thousand, one hundred eleven".