1121223220 has 48 divisors (see below), whose sum is σ = 2560855248. Its totient is φ = 409881600.

The previous prime is 1121223199. The next prime is 1121223223. The reversal of 1121223220 is 223221211.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 34597924 + 1086625296 = 5882^2 + 32964^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1121223194 and 1121223203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1121223223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4912 + ... + 47608.

It is an arithmetic number, because the mean of its divisors is an integer number (53351151).

Almost surely, 2^1121223220 is an apocalyptic number.

1121223220 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 1121223220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1280427624).

1121223220 is an abundant number, since it is smaller than the sum of its proper divisors (1439632028).

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

1121223220 is a wasteful number, since it uses less digits than its factorization.

1121223220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42820 (or 42818 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 1121223220 is about 33484.6714184267. The cubic root of 1121223220 is about 1038.8767520207.

Adding to 1121223220 its reverse (223221211), we get a palindrome (1344444431).

The spelling of 1121223220 in words is "one billion, one hundred twenty-one million, two hundred twenty-three thousand, two hundred twenty".