278455680709 has 2 divisors, whose sum is σ = 278455680710. Its totient is φ = 278455680708.

The previous prime is 278455680707. The next prime is 278455680739. The reversal of 278455680709 is 907086554872.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 277586728225 + 868952484 = 526865^2 + 29478^2 .

It is a cyclic number.

It is not a de Polignac number, because 278455680709 - 2¹ = 278455680707 is a prime.

It is a super-2 number, since 2×278455680709² (a number of 24 digits) contains 22 as substring.

Together with 278455680707, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (278455680707) 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 as a sum of consecutive naturals, namely, 139227840354 + 139227840355.

It is an arithmetic number, because the mean of its divisors is an integer number (139227840355).

Almost surely, 2^278455680709 is an apocalyptic number.

It is an amenable number.

278455680709 is a deficient number, since it is larger than the sum of its proper divisors (1).

278455680709 is an equidigital number, since it uses as much as digits as its factorization.

278455680709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 33868800, while the sum is 61.

The spelling of 278455680709 in words is "two hundred seventy-eight billion, four hundred fifty-five million, six hundred eighty thousand, seven hundred nine".