678323548817 has 2 divisors, whose sum is σ = 678323548818. Its totient is φ = 678323548816.

The previous prime is 678323548787. The next prime is 678323548823. The reversal of 678323548817 is 718845323876.

It is a Cunningham number, because it is equal to 823604²+1.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 678323548816 + 1 = 823604^2 + 1^2 .

It is a cyclic number.

It is not a de Polignac number, because 678323548817 - 2⁸ = 678323548561 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 678323548817.

It is not a weakly prime, because it can be changed into another prime (678323548867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339161774408 + 339161774409.

It is an arithmetic number, because the mean of its divisors is an integer number (339161774409).

Almost surely, 2^678323548817 is an apocalyptic number.

It is an amenable number.

678323548817 is a deficient number, since it is larger than the sum of its proper divisors (1).

678323548817 is an equidigital number, since it uses as much as digits as its factorization.

678323548817 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 54190080, while the sum is 62.

The spelling of 678323548817 in words is "six hundred seventy-eight billion, three hundred twenty-three million, five hundred forty-eight thousand, eight hundred seventeen".