68735209 has 2 divisors, whose sum is σ = 68735210. Its totient is φ = 68735208.

The previous prime is 68735207. The next prime is 68735221. The reversal of 68735209 is 90253786.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 36869184 + 31866025 = 6072^2 + 5645^2 .

It is a cyclic number.

It is not a de Polignac number, because 68735209 - 2¹ = 68735207 is a prime.

Together with 68735207, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (68735203) 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, 34367604 + 34367605.

It is an arithmetic number, because the mean of its divisors is an integer number (34367605).

Almost surely, 2^68735209 is an apocalyptic number.

It is an amenable number.

68735209 is a deficient number, since it is larger than the sum of its proper divisors (1).

68735209 is an equidigital number, since it uses as much as digits as its factorization.

68735209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90720, while the sum is 40.

The square root of 68735209 is about 8290.6699970509. The cubic root of 68735209 is about 409.6312548153.

The spelling of 68735209 in words is "sixty-eight million, seven hundred thirty-five thousand, two hundred nine".