111111221100 has 144 divisors (see below), whose sum is σ = 354180830976. Its totient is φ = 26669280000.

The previous prime is 111111221083. The next prime is 111111221119. The reversal of 111111221100 is 1122111111.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a zygodrome in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 166617 + ... + 499983.

It is an arithmetic number, because the mean of its divisors is an integer number (2459589104).

Almost surely, 2^111111221100 is an apocalyptic number.

111111221100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 111111221100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (177090415488).

111111221100 is an abundant number, since it is smaller than the sum of its proper divisors (243069609876).

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

111111221100 is a wasteful number, since it uses less digits than its factorization.

111111221100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333496 (or 333489 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 12.

Adding to 111111221100 its reverse (1122111111), we get a palindrome (112233332211).

It can be divided in two parts, 1111 and 11221100, that added together give a palindrome (11222211).

The spelling of 111111221100 in words is "one hundred eleven billion, one hundred eleven million, two hundred twenty-one thousand, one hundred".