11111200020 has 144 divisors (see below), whose sum is σ = 34360998672. Its totient is φ = 2905528320.

The previous prime is 11111200013. The next prime is 11111200021. The reversal of 11111200020 is 2000211111.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 2883204 + 11108316816 = 1698^2 + 105396^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 11111199975 and 11111200011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11111200021) 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, 4094184 + ... + 4096896.

Almost surely, 2^11111200020 is an apocalyptic number.

11111200020 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 11111200020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17180499336).

11111200020 is an abundant number, since it is smaller than the sum of its proper divisors (23249798652).

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

11111200020 is a wasteful number, since it uses less digits than its factorization.

11111200020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3162 (or 3157 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 11111200020 its reverse (2000211111), we get a palindrome (13111411131).

The spelling of 11111200020 in words is "eleven billion, one hundred eleven million, two hundred thousand, twenty".