1221440331144 has 256 divisors, whose sum is σ = 3456649728000. Its totient is φ = 356482365440.

The previous prime is 1221440331127. The next prime is 1221440331169. The reversal of 1221440331144 is 4411330441221.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 277031212 + ... + 277035620.

It is an arithmetic number, because the mean of its divisors is an integer number (13502538000).

Almost surely, 2^{1221440331144} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221440331144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1728324864000).

1221440331144 is an abundant number, since it is smaller than the sum of its proper divisors (2235209396856).

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

1221440331144 is a wasteful number, since it uses less digits than its factorization.

1221440331144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4828 (or 4824 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 30.

Adding to 1221440331144 its reverse (4411330441221), we get a palindrome (5632770772365).

The spelling of 1221440331144 in words is "one trillion, two hundred twenty-one billion, four hundred forty million, three hundred thirty-one thousand, one hundred forty-four".