678400067 has 2 divisors, whose sum is σ = 678400068. Its totient is φ = 678400066.

The previous prime is 678400061. The next prime is 678400109. The reversal of 678400067 is 760004876.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 678400067 - 2¹⁸ = 678137923 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 678400067.

It is not a weakly prime, because it can be changed into another prime (678400061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339200033 + 339200034.

It is an arithmetic number, because the mean of its divisors is an integer number (339200034).

Almost surely, 2^678400067 is an apocalyptic number.

678400067 is a deficient number, since it is larger than the sum of its proper divisors (1).

678400067 is an equidigital number, since it uses as much as digits as its factorization.

678400067 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 56448, while the sum is 38.

The square root of 678400067 is about 26046.1142399399. The cubic root of 678400067 is about 878.6757229376.

The spelling of 678400067 in words is "six hundred seventy-eight million, four hundred thousand, sixty-seven".