11111212212111 has 48 divisors (see below), whose sum is σ = 17537588640000. Its totient is φ = 6722918991360.

The previous prime is 11111212212101. The next prime is 11111212212119. The reversal of 11111212212111 is 11121221211111.

11111212212111 is a `hidden beast` number, since 1 + 111 + 121 + 221 + 211 + 1 = 666.

It is not a de Polignac number, because 11111212212111 - 2⁶ = 11111212212047 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11111212212119) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 146735886 + ... + 146811588.

It is an arithmetic number, because the mean of its divisors is an integer number (365366430000).

Almost surely, 2^{11111212212111} is an apocalyptic number.

11111212212111 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

11111212212111 is a deficient number, since it is larger than the sum of its proper divisors (6426376427889).

11111212212111 is a wasteful number, since it uses less digits than its factorization.

11111212212111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78156 (or 78153 counting only the distinct ones).

The product of its digits is 16, while the sum is 18.

Adding to 11111212212111 its reverse (11121221211111), we get a palindrome (22232433423222).

It can be divided in two parts, 11 and 111212212111, that multiplied together give a palindrome (1223334333221).

The spelling of 11111212212111 in words is "eleven trillion, one hundred eleven billion, two hundred twelve million, two hundred twelve thousand, one hundred eleven".