1287989564544 has 192 divisors, whose sum is σ = 3937939551000. Its totient is φ = 404073381888.

The previous prime is 1287989564513. The next prime is 1287989564599. The reversal of 1287989564544 is 4454659897821.

It is a happy number.

1287989564544 is a `hidden beast` number, since 1 + 2 + 8 + 7 + 9 + 8 + 9 + 564 + 54 + 4 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 797306126400 + 490683438144 = 892920^2 + 700488^2 .

It is a tau number, because it is divible by the number of its divisors (192).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5545992 + ... + 5773560.

Almost surely, 2^{1287989564544} 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 1287989564544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1968969775500).

1287989564544 is an abundant number, since it is smaller than the sum of its proper divisors (2649949986456).

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

1287989564544 is an equidigital number, since it uses as much as digits as its factorization.

1287989564544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227640 (or 227591 counting only the distinct ones).

The product of its digits is 696729600, while the sum is 72.

The spelling of 1287989564544 in words is "one trillion, two hundred eighty-seven billion, nine hundred eighty-nine million, five hundred sixty-four thousand, five hundred forty-four".