68178809 has 2 divisors, whose sum is σ = 68178810. Its totient is φ = 68178808.

The previous prime is 68178791. The next prime is 68178839. The reversal of 68178809 is 90887186.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38093584 + 30085225 = 6172^2 + 5485^2 .

It is a cyclic number.

It is not a de Polignac number, because 68178809 - 2¹² = 68174713 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (68178839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34089404 + 34089405.

It is an arithmetic number, because the mean of its divisors is an integer number (34089405).

Almost surely, 2^68178809 is an apocalyptic number.

It is an amenable number.

68178809 is a deficient number, since it is larger than the sum of its proper divisors (1).

68178809 is an equidigital number, since it uses as much as digits as its factorization.

68178809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 193536, while the sum is 47.

The square root of 68178809 is about 8257.0460214292. The cubic root of 68178809 is about 408.5229601366.

The spelling of 68178809 in words is "sixty-eight million, one hundred seventy-eight thousand, eight hundred nine".