1278543212605 has 16 divisors (see below), whose sum is σ = 1543091203584. Its totient is φ = 1016953335360.

The previous prime is 1278543212591. The next prime is 1278543212647. The reversal of 1278543212605 is 5062123458721.

It is not a de Polignac number, because 1278543212605 - 2¹⁹ = 1278542688317 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 148995 + ... + 1606015.

It is an arithmetic number, because the mean of its divisors is an integer number (96443200224).

Almost surely, 2^{1278543212605} is an apocalyptic number.

It is an amenable number.

1278543212605 is a deficient number, since it is larger than the sum of its proper divisors (264547990979).

1278543212605 is a wasteful number, since it uses less digits than its factorization.

1278543212605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1458036.

The product of its (nonzero) digits is 806400, while the sum is 46.

The spelling of 1278543212605 in words is "one trillion, two hundred seventy-eight billion, five hundred forty-three million, two hundred twelve thousand, six hundred five".