1278240531648 has 224 divisors, whose sum is σ = 3551881095360. Its totient is φ = 405169766400.

The previous prime is 1278240531643. The next prime is 1278240531713. The reversal of 1278240531648 is 8461350428721.

It is a Cunningham number, because it is equal to 1130593²-1.

It is a self number, because there is not a number n which added to its sum of digits gives 1278240531648.

It is not an unprimeable number, because it can be changed into a prime (1278240531643) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 108531136 + ... + 108542912.

Almost surely, 2^{1278240531648} 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 1278240531648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1775940547680).

1278240531648 is an abundant number, since it is smaller than the sum of its proper divisors (2273640563712).

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

1278240531648 is a wasteful number, since it uses less digits than its factorization.

1278240531648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12115 (or 12105 counting only the distinct ones).

The product of its (nonzero) digits is 2580480, while the sum is 51.

The spelling of 1278240531648 in words is "one trillion, two hundred seventy-eight billion, two hundred forty million, five hundred thirty-one thousand, six hundred forty-eight".