11001001220 has 96 divisors (see below), whose sum is σ = 25588846080. Its totient is φ = 3939287040.

The previous prime is 11001001213. The next prime is 11001001241. The reversal of 11001001220 is 2210010011.

It is a junction number, because it is equal to n+sod(n) for n = 11001001198 and 11001001207.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10027712 + ... + 10028808.

It is an arithmetic number, because the mean of its divisors is an integer number (266550480).

Almost surely, 2^11001001220 is an apocalyptic number.

11001001220 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 11001001220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12794423040).

11001001220 is an abundant number, since it is smaller than the sum of its proper divisors (14587844860).

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

11001001220 is a wasteful number, since it uses less digits than its factorization.

11001001220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1773 (or 1771 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 11001001220 its reverse (2210010011), we get a palindrome (13211011231).

The spelling of 11001001220 in words is "eleven billion, one million, one thousand, two hundred twenty".