11131221100 has 72 divisors (see below), whose sum is σ = 24579208080. Its totient is φ = 4374881280.

The previous prime is 11131221097. The next prime is 11131221103. The reversal of 11131221100 is 112213111.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (11131221097) and next prime (11131221103).

It is not an unprimeable number, because it can be changed into a prime (11131221103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1446864 + ... + 1454536.

It is an arithmetic number, because the mean of its divisors is an integer number (341377890).

Almost surely, 2^11131221100 is an apocalyptic number.

11131221100 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 11131221100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12289604040).

11131221100 is an abundant number, since it is smaller than the sum of its proper divisors (13447986980).

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

11131221100 is a wasteful number, since it uses less digits than its factorization.

11131221100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7939 (or 7932 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 13.

Adding to 11131221100 its reverse (112213111), we get a palindrome (11243434211).

The spelling of 11131221100 in words is "eleven billion, one hundred thirty-one million, two hundred twenty-one thousand, one hundred".