11111211221200 has 30 divisors (see below), whose sum is σ = 26694684959894. Its totient is φ = 4444484488320.

The previous prime is 11111211221107. The next prime is 11111211221261. The reversal of 11111211221200 is 212211211111.

It can be written as a sum of positive squares in 3 ways, for example, as 2160535455376 + 8950675765824 = 1469876^2 + 2991768^2 .

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 13889013627 + ... + 13889014426.

Almost surely, 2^{11111211221200} is an apocalyptic number.

11111211221200 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11111211221200 is an abundant number, since it is smaller than the sum of its proper divisors (15583473738694).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

11111211221200 is a wasteful number, since it uses less digits than its factorization.

11111211221200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27778028071 (or 27778028060 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 16.

Adding to 11111211221200 its reverse (212211211111), we get a palindrome (11323422432311).

The spelling of 11111211221200 in words is "eleven trillion, one hundred eleven billion, two hundred eleven million, two hundred twenty-one thousand, two hundred".