68730521 has 2 divisors, whose sum is σ = 68730522. Its totient is φ = 68730520.

The previous prime is 68730511. The next prime is 68730527. The reversal of 68730521 is 12503786.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38875225 + 29855296 = 6235^2 + 5464^2 .

It is a cyclic number.

It is not a de Polignac number, because 68730521 - 2¹⁸ = 68468377 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 (68730527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34365260 + 34365261.

It is an arithmetic number, because the mean of its divisors is an integer number (34365261).

Almost surely, 2^68730521 is an apocalyptic number.

It is an amenable number.

68730521 is a deficient number, since it is larger than the sum of its proper divisors (1).

68730521 is an equidigital number, since it uses as much as digits as its factorization.

68730521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 68730521 is about 8290.3872647784. The cubic root of 68730521 is about 409.6219418057.

The spelling of 68730521 in words is "sixty-eight million, seven hundred thirty thousand, five hundred twenty-one".