1311636278987 has 4 divisors (see below), whose sum is σ = 1323243679800. Its totient is φ = 1300028878176.

The previous prime is 1311636278977. The next prime is 1311636279001. The reversal of 1311636278987 is 7898726361131.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1311636278987 - 2⁴ = 1311636278971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1311636278977) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5803700237 + ... + 5803700462.

It is an arithmetic number, because the mean of its divisors is an integer number (330810919950).

Almost surely, 2^{1311636278987} is an apocalyptic number.

1311636278987 is a deficient number, since it is larger than the sum of its proper divisors (11607400813).

1311636278987 is a wasteful number, since it uses less digits than its factorization.

1311636278987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11607400812.

The product of its digits is 18289152, while the sum is 62.

The spelling of 1311636278987 in words is "one trillion, three hundred eleven billion, six hundred thirty-six million, two hundred seventy-eight thousand, nine hundred eighty-seven".