1278686868781 has 8 divisors (see below), whose sum is σ = 1463796086400. Its totient is φ = 1094187567408.

The previous prime is 1278686868769. The next prime is 1278686868803. The reversal of 1278686868781 is 1878686868721.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1278686868781 - 2¹⁹ = 1278686344493 is a prime.

It is a super-2 number, since 2×1278686868781² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1278686868698 and 1278686868707.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1278686868721) 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 7 ways as a sum of consecutive naturals, for example, 152474566 + ... + 152482951.

It is an arithmetic number, because the mean of its divisors is an integer number (182974510800).

Almost surely, 2^{1278686868781} is an apocalyptic number.

It is an amenable number.

1278686868781 is a deficient number, since it is larger than the sum of its proper divisors (185109217619).

1278686868781 is an equidigital number, since it uses as much as digits as its factorization.

1278686868781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304958123.

The product of its digits is 693633024, while the sum is 76.

The spelling of 1278686868781 in words is "one trillion, two hundred seventy-eight billion, six hundred eighty-six million, eight hundred sixty-eight thousand, seven hundred eighty-one".