13987966978991 has 2 divisors, whose sum is σ = 13987966978992. Its totient is φ = 13987966978990.

The previous prime is 13987966978969. The next prime is 13987966979093. The reversal of 13987966978991 is 19987966978931.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 13987966978991 - 2¹⁰ = 13987966977967 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 13987966978991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13987966977991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6993983489495 + 6993983489496.

It is an arithmetic number, because the mean of its divisors is an integer number (6993983489496).

Almost surely, 2^{13987966978991} is an apocalyptic number.

13987966978991 is a deficient number, since it is larger than the sum of its proper divisors (1).

13987966978991 is an equidigital number, since it uses as much as digits as its factorization.

13987966978991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 19999187712, while the sum is 92.

The spelling of 13987966978991 in words is "thirteen trillion, nine hundred eighty-seven billion, nine hundred sixty-six million, nine hundred seventy-eight thousand, nine hundred ninety-one".