68390305 has 4 divisors (see below), whose sum is σ = 82068372. Its totient is φ = 54712240.

The previous prime is 68390297. The next prime is 68390321. The reversal of 68390305 is 50309386.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10751841 + 57638464 = 3279^2 + 7592^2 .

It is not a de Polignac number, because 68390305 - 2³ = 68390297 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 6839026 + ... + 6839035.

It is an arithmetic number, because the mean of its divisors is an integer number (20517093).

Almost surely, 2^68390305 is an apocalyptic number.

It is an amenable number.

68390305 is a deficient number, since it is larger than the sum of its proper divisors (13678067).

68390305 is a wasteful number, since it uses less digits than its factorization.

68390305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13678066.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 68390305 is about 8269.8431061296. The cubic root of 68390305 is about 408.9449474864.

The spelling of 68390305 in words is "sixty-eight million, three hundred ninety thousand, three hundred five".