278371355617 has 2 divisors, whose sum is σ = 278371355618. Its totient is φ = 278371355616.

The previous prime is 278371355611. The next prime is 278371355657. The reversal of 278371355617 is 716553173872.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 265151875041 + 13219480576 = 514929^2 + 114976^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-278371355617 is a prime.

It is a super-2 number, since 2×278371355617² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (278371355611) 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, 139185677808 + 139185677809.

It is an arithmetic number, because the mean of its divisors is an integer number (139185677809).

Almost surely, 2^278371355617 is an apocalyptic number.

It is an amenable number.

278371355617 is a deficient number, since it is larger than the sum of its proper divisors (1).

278371355617 is an equidigital number, since it uses as much as digits as its factorization.

278371355617 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7408800, while the sum is 55.

The spelling of 278371355617 in words is "two hundred seventy-eight billion, three hundred seventy-one million, three hundred fifty-five thousand, six hundred seventeen".