1100221220 has 96 divisors (see below), whose sum is σ = 2844441600. Its totient is φ = 349017984.

The previous prime is 1100221219. The next prime is 1100221319. The reversal of 1100221220 is 221220011.

It is a happy number.

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, 109571 + ... + 119189.

It is an arithmetic number, because the mean of its divisors is an integer number (29629600).

Almost surely, 2^1100221220 is an apocalyptic number.

1100221220 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 1100221220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1422220800).

1100221220 is an abundant number, since it is smaller than the sum of its proper divisors (1744220380).

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

1100221220 is a wasteful number, since it uses less digits than its factorization.

1100221220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9697 (or 9695 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 1100221220 is about 33169.5827528777. The cubic root of 1100221220 is about 1032.3493111231.

Adding to 1100221220 its reverse (221220011), we get a palindrome (1321441231).

The spelling of 1100221220 in words is "one billion, one hundred million, two hundred twenty-one thousand, two hundred twenty".