1111221220 has 24 divisors (see below), whose sum is σ = 2337633144. Its totient is φ = 443713536.

The previous prime is 1111221203. The next prime is 1111221229. The reversal of 1111221220 is 221221111.

It can be written as a sum of positive squares in 4 ways, for example, as 434388964 + 676832256 = 20842^2 + 26016^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1111221220.

It is not an unprimeable number, because it can be changed into a prime (1111221229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36607 + ... + 59686.

It is an arithmetic number, because the mean of its divisors is an integer number (97401381).

Almost surely, 2^1111221220 is an apocalyptic number.

1111221220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1111221220 is an abundant number, since it is smaller than the sum of its proper divisors (1226411924).

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

1111221220 is a wasteful number, since it uses less digits than its factorization.

1111221220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96879 (or 96877 counting only the distinct ones).

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

The square root of 1111221220 is about 33334.9849257503. The cubic root of 1111221220 is about 1035.7783809131.

Adding to 1111221220 its reverse (221221111), we get a palindrome (1332442331).

The spelling of 1111221220 in words is "one billion, one hundred eleven million, two hundred twenty-one thousand, two hundred twenty".