1321440252544 has 128 divisors (see below), whose sum is σ = 2826695808000. Its totient is φ = 613455068160.

The previous prime is 1321440252527. The next prime is 1321440252607. The reversal of 1321440252544 is 4452520441231.

It is a tau number, because it is divible by the number of its divisors (128).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47480617 + ... + 47508439.

It is an arithmetic number, because the mean of its divisors is an integer number (22083561000).

Almost surely, 2^{1321440252544} 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 1321440252544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1413347904000).

1321440252544 is an abundant number, since it is smaller than the sum of its proper divisors (1505255555456).

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

1321440252544 is a wasteful number, since it uses less digits than its factorization.

1321440252544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28246 (or 28234 counting only the distinct ones).

The product of its (nonzero) digits is 153600, while the sum is 37.

Adding to 1321440252544 its reverse (4452520441231), we get a palindrome (5773960693775).

The spelling of 1321440252544 in words is "one trillion, three hundred twenty-one billion, four hundred forty million, two hundred fifty-two thousand, five hundred forty-four".