1278506679 has 4 divisors (see below), whose sum is σ = 1704675576. Its totient is φ = 852337784.

The previous prime is 1278506639. The next prime is 1278506701. The reversal of 1278506679 is 9766058721.

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 1278506679 - 2⁸ = 1278506423 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1278506639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 213084444 + ... + 213084449.

It is an arithmetic number, because the mean of its divisors is an integer number (426168894).

Almost surely, 2^1278506679 is an apocalyptic number.

1278506679 is a deficient number, since it is larger than the sum of its proper divisors (426168897).

1278506679 is an equidigital number, since it uses as much as digits as its factorization.

1278506679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 426168896.

The product of its (nonzero) digits is 1270080, while the sum is 51.

The square root of 1278506679 is about 35756.2117540435. The cubic root of 1278506679 is about 1085.3446430756.

The spelling of 1278506679 in words is "one billion, two hundred seventy-eight million, five hundred six thousand, six hundred seventy-nine".