1221112111100 has 36 divisors (see below), whose sum is σ = 3028358037264. Its totient is φ = 418667009280.

The previous prime is 1221112111039. The next prime is 1221112111171. The reversal of 1221112111100 is 11112111221.

It is a super-2 number, since 2×1221112111100² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 872222237 + ... + 872223636.

Almost surely, 2^{1221112111100} is an apocalyptic number.

1221112111100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221112111100 is an abundant number, since it is smaller than the sum of its proper divisors (1807245926164).

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

1221112111100 is a wasteful number, since it uses less digits than its factorization.

1221112111100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1744445894 (or 1744445887 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 1221112111100 its reverse (11112111221), we get a palindrome (1232224222321).

It can be divided in two parts, 12211121 and 11100, that added together give a palindrome (12222221).

The spelling of 1221112111100 in words is "one trillion, two hundred twenty-one billion, one hundred twelve million, one hundred eleven thousand, one hundred".