11111221121100 has 288 divisors, whose sum is σ = 33354265190400. Its totient is φ = 2852471731200.

The previous prime is 11111221121023. The next prime is 11111221121101. The reversal of 11111221121100 is 112112211111.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 11111221121100.

It is not an unprimeable number, because it can be changed into a prime (11111221121101) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 6316782021 + ... + 6316783779.

It is an arithmetic number, because the mean of its divisors is an integer number (115813420800).

Almost surely, 2^{11111221121100} is an apocalyptic number.

11111221121100 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 11111221121100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16677132595200).

11111221121100 is an abundant number, since it is smaller than the sum of its proper divisors (22243044069300).

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

11111221121100 is a wasteful number, since it uses less digits than its factorization.

11111221121100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3513 (or 3506 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 15.

Adding to 11111221121100 its reverse (112112211111), we get a palindrome (11223333332211).

The spelling of 11111221121100 in words is "eleven trillion, one hundred eleven billion, two hundred twenty-one million, one hundred twenty-one thousand, one hundred".