21120011101111 has 16 divisors (see below), whose sum is σ = 24859402944768. Its totient is φ = 17756716377600.

The previous prime is 21120011101051. The next prime is 21120011101171. The reversal of 21120011101111 is 11110111002112.

It is an interprime number because it is at equal distance from previous prime (21120011101051) and next prime (21120011101171).

It is a cyclic number.

It is not a de Polignac number, because 21120011101111 - 2¹⁷ = 21120010970039 is a prime.

It is a super-2 number, since 2×21120011101111² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21120011101091 and 21120011101100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120011101171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1541374780 + ... + 1541388481.

It is an arithmetic number, because the mean of its divisors is an integer number (1553712684048).

Almost surely, 2^{21120011101111} is an apocalyptic number.

21120011101111 is a deficient number, since it is larger than the sum of its proper divisors (3739391843657).

21120011101111 is a wasteful number, since it uses less digits than its factorization.

21120011101111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3082763322.

The product of its (nonzero) digits is 4, while the sum is 13.

Adding to 21120011101111 its reverse (11110111002112), we get a palindrome (32230122103223).

The spelling of 21120011101111 in words is "twenty-one trillion, one hundred twenty billion, eleven million, one hundred one thousand, one hundred eleven".