68731009 has 2 divisors, whose sum is σ = 68731010. Its totient is φ = 68731008.

The previous prime is 68731001. The next prime is 68731043. The reversal of 68731009 is 90013786.

It is an a-pointer prime, because the next prime (68731043) can be obtained adding 68731009 to its sum of digits (34).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 50481025 + 18249984 = 7105^2 + 4272^2 .

It is a cyclic number.

It is not a de Polignac number, because 68731009 - 2³ = 68731001 is a prime.

It is not a weakly prime, because it can be changed into another prime (68731001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34365504 + 34365505.

It is an arithmetic number, because the mean of its divisors is an integer number (34365505).

Almost surely, 2^68731009 is an apocalyptic number.

It is an amenable number.

68731009 is a deficient number, since it is larger than the sum of its proper divisors (1).

68731009 is an equidigital number, since it uses as much as digits as its factorization.

68731009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9072, while the sum is 34.

The square root of 68731009 is about 8290.4166964031. The cubic root of 68731009 is about 409.6229112684.

The spelling of 68731009 in words is "sixty-eight million, seven hundred thirty-one thousand, nine".