1287744968538 has 192 divisors, whose sum is σ = 3418520371200. Its totient is φ = 358149224160.

The previous prime is 1287744968533. The next prime is 1287744968551. The reversal of 1287744968538 is 8358694477821.

It is a happy number.

1287744968538 is a `hidden beast` number, since 1 + 2 + 8 + 77 + 449 + 6 + 85 + 38 = 666.

It is not an unprimeable number, because it can be changed into a prime (1287744968533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 14798031 + ... + 14884797.

It is an arithmetic number, because the mean of its divisors is an integer number (17804793600).

Almost surely, 2^{1287744968538} is an apocalyptic number.

1287744968538 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1287744968538, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1709260185600).

1287744968538 is an abundant number, since it is smaller than the sum of its proper divisors (2130775402662).

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

1287744968538 is a wasteful number, since it uses less digits than its factorization.

1287744968538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86942 (or 86929 counting only the distinct ones).

The product of its digits is 650280960, while the sum is 72.

The spelling of 1287744968538 in words is "one trillion, two hundred eighty-seven billion, seven hundred forty-four million, nine hundred sixty-eight thousand, five hundred thirty-eight".