11121021220 has 96 divisors (see below), whose sum is σ = 24779768832. Its totient is φ = 4185600000.

The previous prime is 11121021199. The next prime is 11121021227. The reversal of 11121021220 is 2212012111.

It is a super-2 number, since 2×11121021220² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 11121021220.

It is not an unprimeable number, because it can be changed into a prime (11121021227) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10192875 + ... + 10193965.

It is an arithmetic number, because the mean of its divisors is an integer number (258122592).

Almost surely, 2^11121021220 is an apocalyptic number.

11121021220 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 11121021220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12389884416).

11121021220 is an abundant number, since it is smaller than the sum of its proper divisors (13658747612).

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

11121021220 is a wasteful number, since it uses less digits than its factorization.

11121021220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1573 (or 1571 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 11121021220 its reverse (2212012111), we get a palindrome (13333033331).

The spelling of 11121021220 in words is "eleven billion, one hundred twenty-one million, twenty-one thousand, two hundred twenty".