68778109 has 2 divisors, whose sum is σ = 68778110. Its totient is φ = 68778108.

The previous prime is 68778103. The next prime is 68778121. The reversal of 68778109 is 90187786.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 54715609 + 14062500 = 7397^2 + 3750^2 .

It is a cyclic number.

It is not a de Polignac number, because 68778109 - 2⁵ = 68778077 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68778103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34389054 + 34389055.

It is an arithmetic number, because the mean of its divisors is an integer number (34389055).

Almost surely, 2^68778109 is an apocalyptic number.

It is an amenable number.

68778109 is a deficient number, since it is larger than the sum of its proper divisors (1).

68778109 is an equidigital number, since it uses as much as digits as its factorization.

68778109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 169344, while the sum is 46.

The square root of 68778109 is about 8293.2568391435. The cubic root of 68778109 is about 409.7164587272.

The spelling of 68778109 in words is "sixty-eight million, seven hundred seventy-eight thousand, one hundred nine".