1278326066057 has 4 divisors (see below), whose sum is σ = 1278879695940. Its totient is φ = 1277772436176.

The previous prime is 1278326066053. The next prime is 1278326066063. The reversal of 1278326066057 is 7506606238721.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1138102778761 + 140223287296 = 1066819^2 + 374464^2 .

It is a cyclic number.

It is not a de Polignac number, because 1278326066057 - 2² = 1278326066053 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1278326066053) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 276811478 + ... + 276816095.

It is an arithmetic number, because the mean of its divisors is an integer number (319719923985).

Almost surely, 2^{1278326066057} is an apocalyptic number.

It is an amenable number.

1278326066057 is a deficient number, since it is larger than the sum of its proper divisors (553629883).

1278326066057 is an equidigital number, since it uses as much as digits as its factorization.

1278326066057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 553629882.

The product of its (nonzero) digits is 5080320, while the sum is 53.

The spelling of 1278326066057 in words is "one trillion, two hundred seventy-eight billion, three hundred twenty-six million, sixty-six thousand, fifty-seven".