1287876391290 has 48 divisors (see below), whose sum is σ = 3349758740328. Its totient is φ = 343302409728.

The previous prime is 1287876391283. The next prime is 1287876391343. The reversal of 1287876391290 is 921936787821.

1287876391290 is a `hidden beast` number, since 1 + 2 + 87 + 87 + 6 + 391 + 2 + 90 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1037275030089 + 250601361201 = 1018467^2 + 500601^2 .

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 2498467 + ... + 2969526.

Almost surely, 2^{1287876391290} is an apocalyptic number.

1287876391290 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1287876391290 is an abundant number, since it is smaller than the sum of its proper divisors (2061882349038).

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

1287876391290 is a wasteful number, since it uses less digits than its factorization.

1287876391290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5470623 (or 5470620 counting only the distinct ones).

The product of its (nonzero) digits is 18289152, while the sum is 63.

The spelling of 1287876391290 in words is "one trillion, two hundred eighty-seven billion, eight hundred seventy-six million, three hundred ninety-one thousand, two hundred ninety".