1121221220 has 48 divisors (see below), whose sum is σ = 2694263040. Its totient is φ = 383942784.

The previous prime is 1121221183. The next prime is 1121221223. The reversal of 1121221220 is 221221211.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 1121221195 and 1121221204.

It is not an unprimeable number, because it can be changed into a prime (1121221223) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 119666 + ... + 128694.

It is an arithmetic number, because the mean of its divisors is an integer number (56130480).

Almost surely, 2^1121221220 is an apocalyptic number.

1121221220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1121221220 is an abundant number, since it is smaller than the sum of its proper divisors (1573041820).

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

1121221220 is a wasteful number, since it uses less digits than its factorization.

1121221220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9932 (or 9930 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 1121221220 is about 33484.6415540020. The cubic root of 1121221220 is about 1038.8761343160.

Adding to 1121221220 its reverse (221221211), we get a palindrome (1342442431).

Subtracting from 1121221220 its reverse (221221211), we obtain a palindrome (900000009).

The spelling of 1121221220 in words is "one billion, one hundred twenty-one million, two hundred twenty-one thousand, two hundred twenty".