1121221644 has 24 divisors (see below), whose sum is σ = 2645581680. Its totient is φ = 369540864.

The previous prime is 1121221643. The next prime is 1121221669. The reversal of 1121221644 is 4461221211.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (1121221643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 523849 + ... + 525984.

It is an arithmetic number, because the mean of its divisors is an integer number (110232570).

Almost surely, 2^1121221644 is an apocalyptic number.

It is an amenable number.

1121221644 is an abundant number, since it is smaller than the sum of its proper divisors (1524360036).

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

1121221644 is a wasteful number, since it uses less digits than its factorization.

1121221644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1049929 (or 1049927 counting only the distinct ones).

The product of its digits is 768, while the sum is 24.

The square root of 1121221644 is about 33484.6478852623. The cubic root of 1121221644 is about 1038.8762652694.

Adding to 1121221644 its reverse (4461221211), we get a palindrome (5582442855).

The spelling of 1121221644 in words is "one billion, one hundred twenty-one million, two hundred twenty-one thousand, six hundred forty-four".